I love the names [name_m]Ulysses[/name_m], [name_u]Neptune[/name_u] & Seabrook(e) for a boy…can any lovely Nameberries suggest equivalent girl waterbaby names that evoke the sea/ water/ mermaids etc? Thanx 
[name_u]Ariel[/name_u] 
[name_m]Just[/name_m] kidding lol. But [name_u]Ariel[/name_u] is a great name. Hmm, let me think…
[name_f]Cordelia[/name_f] - “heart; daughter of the sea”
[name_f]Doris[/name_f] - “gift of the ocean”
[name_f]Marissa[/name_f] - “of the sea”
[name_f]Marin[/name_f] - “of the sea”
[name_f]Talia[/name_f] - “gentle dew from heaven”
[name_f]Tallulah[/name_f] - “lady of abundance or leaping water”
[name_f]Topanga[/name_f] - “where the mountain meets the sea”
[name_f]Ula[/name_f] - “gem of the sea”
Some other names that may not be water/ocean/mermaid related, but I feel like mermaids would have these names are…
[name_f]Kira[/name_f]
[name_u]Shelly[/name_u]
[name_f]Michelle[/name_f]
[name_f]Nora[/name_f]
[name_f]Melody[/name_f]
[name_f]Felicity[/name_f]
[name_f]Gemma[/name_f]
[name_f]Mia[/name_f]
[name_f]Stella[/name_f]
[name_u]Vesper[/name_u]
[name_f]Mirella[/name_f]
[name_u]Kalani[/name_u]
[name_f]Cordelia[/name_f] - “heart; daughter of the sea”
[name_f]Doris[/name_f] - “gift of the ocean”
[name_f]Marissa[/name_f] - “of the sea”
[name_f]Marin[/name_f] - “of the sea”
[name_f]Talia[/name_f] - “gentle dew from heaven”
[name_f]Tallulah[/name_f] - “lady of abundance or leaping water”
[name_f]Topanga[/name_f] - “where the mountain meets the sea”
[name_f]Ula[/name_f] - “gem of the sea”
Some other names that may not be water/ocean/mermaid related, but I feel like mermaids would have these names are…
[name_f]Kira[/name_f]
[name_u]Shelly[/name_u]
[name_f]Michelle[/name_f]
[name_f]Nora[/name_f]
[name_f]Melody[/name_f]
[name_f]Felicity[/name_f]
[name_f]Gemma[/name_f]
[name_f]Mia[/name_f]
[name_f]Stella[/name_f]
[name_u]Vesper[/name_u]
[name_f]Mirella[/name_f]
[name_u]Kalani[/name_u]
[name_f]Araluen[/name_f] “place of the water lilies”
[name_f]Moselle[/name_f] “drawn from the water”
[name_f]Nahla[/name_f] “drink of water”
[name_f]Tallulah[/name_f] “leaping water”
[name_f]Guinevere[/name_f]/[name_f]Ginevra[/name_f]/[name_f]Gwenore[/name_f] “white wave”
[name_f]Ondine[/name_f]/[name_f]Undine[/name_f] “little wave”
Morwen/[name_f]Morwenna[/name_f] “sea waves”
[name_f]Nixie[/name_f], [name_f]Naida[/name_f], Rusalka (all water nymphs)
[name_f]Sirena[/name_f]/[name_f]Sirene[/name_f] “siren”
[name_f]Lorelei[/name_f], [name_f]Melusine[/name_f] (mermaids in mythology)
I also found these great lists:
[name_f]Thalassa[/name_f] (Ancient water goddess name)
[name_f]Melusine[/name_f] (A mythological water spirit)
[name_f]Sabrina[/name_f] (Latin name for [name_u]River[/name_u] Severn)
[name_f]Ondine[/name_f]/[name_f]Undine[/name_f] (Specific name of a water nymph)
[name_f]Galatea[/name_f] (Another specific name of a sea nymph)
Brizo ([name_f]Goddess[/name_f] of sailors)
[name_f]Viviane[/name_f] (Lady of the [name_u]Lake[/name_u] in Arthurian [name_u]Legend[/name_u])
[name_f]Marina[/name_f] “from the sea”
[name_f]Lorelei[/name_f] (Another female water spirit)
Some other mermaid-y names:
[name_f]Sirena[/name_f]/[name_f]Serena[/name_f]
[name_f]Zora[/name_f]
[name_f]Delphine[/name_f]
[name_u]Gale[/name_u]
[name_f]Neve[/name_f]/[name_f]Neva[/name_f]
[name_f]Cora[/name_f]
[name_f]Isla[/name_f]
[name_f]Marina[/name_f], [name_f]Marine[/name_f], [name_f]Nerissa[/name_f] all mean from the sea.
Tethys- Greek sea goddess
I hadn’t heard of Seabrook before and find it stunning! So unusual yet made of classic components.
[name_f]Nerina[/name_f] - water, sea nymph
[name_f]Marilla[/name_f] - shining sea
[name_f]Darya[/name_f] - sea
[name_f]Lana[/name_f] - calm as still waters
[name_f]Yara[/name_f] - water lady
[name_f]Misty[/name_f]
[name_u]Marlowe[/name_u] - from the hill by the lake
[name_f]Nixie[/name_f] - little water sprite
[name_f]Thalassa[/name_f], [name_f]Ondine[/name_f] and [name_f]Coral[/name_f] are the first water names to come to mind. [name_f]Melusine[/name_f] is also high on my lists, she’s so gorgeous! And Rusalka intrigues me but I got some bad feedback on it from someone with more knowledge about it than me, so I’m a little wary.
I also thought of [name_f]Mayim[/name_f]. And [name_f]Noa[/name_f] which means ‘movement’ but always makes me think of water. Water in general is associated with change and so I think any names with meanings or histories related to that would be apt. [name_f]Anastasia[/name_f] means reborn for example, but I can’t think of any others at the moment.
There’s Morwen and [name_f]Morwenna[/name_f], but also Morvoren which means ‘mermaid’.
[name_f]Moana[/name_f]
[name_f]Meri[/name_f]
Meraud
Océane or [name_f]Oceana[/name_f]
The names of the billow maidens in Norse mythology are mostly unwieldy, but Dufa or my preferred variant Duva are both very sweet. Dufa/Duva means ‘pitching wave’.
I visited a list of water deities on wikipedia, these are the ones that stood out (but check with additional sources!)
Vellamo (also Wellamo) - Finnish
[name_m]Namaka[/name_m] - Hawaiian
Sedna - Inuit
Tiamat - Mesopotamia
[name_f]Anahita[/name_f]
Coventina - [name_m]Romano[/name_m]-British
Saw the Lady of the [name_u]Lake[/name_u] mentioned above as [name_f]Viviane[/name_f], she had many other names as well including [name_f]Nimue[/name_f], Niniane, Nyneve, Niviane, Evienne and [name_u]Vivien[/name_u]. One site I found mentioned that she might be Coventina and explained how the name betrays that (google it!)
Others:
Eidothea - sea nymph, Greek
Thoosa - goddess of swiftness, associated with currents of the sea, Greek
Also, look up different water nymphs, there are hundreds with striking names!
You’ve been given so much help already though!
[name_f]Thalassa[/name_f], [name_f]Marina[/name_f], [name_f]Morwenna[/name_f], [name_f]Oceana[/name_f], [name_f]Pacifica[/name_f], Iluka, [name_f]Pelagia[/name_f], [name_f]Pania[/name_f], [name_f]Mira[/name_f], Ezili, Mazu, [name_f]Delphine[/name_f], [name_f]Delphina[/name_f], Brizo, [name_f]Electra[/name_f], [name_f]Anahita[/name_f], [name_f]Araluen[/name_f], [name_f]Cordelia[/name_f], [name_u]Calypso[/name_u], [name_f]Daphne[/name_f],.
Asherah means She Who Walks on Waves/In the Sea.
Some others:
[name_f]Nimue[/name_f], Nimiane, Niniane, & Nyneve - Various names of the Lady of the [name_u]Lake[/name_u] in Arthurian legend.
[name_f]Nerida[/name_f] - Water [name_f]Lily[/name_f].
[name_f]Maya[/name_f] - Water in Hebrew.
Hanalei - [name_f]Crescent[/name_f] [name_u]Bay[/name_u].
Kainani - Sea of Splendor, Glorious Sea, or Beautiful Sea.
Kainoa - Sea of [name_u]Freedom[/name_u].
Lilinoe - Fine Mist; [name_u]Rain[/name_u].
Puna - [name_f]Spring[/name_f] of Water.
Waiola - Water of Life.
Wailani - [name_f]Heavenly[/name_f] Water.
[name_u]Meredith[/name_u] - Protector of the Sea.
[name_f]Genevieve[/name_f] - White Wave.
[name_f]Nahla[/name_f] - A Drink of Water.
[name_f]Muriel[/name_f] - Shining Sea.
[name_f]Una[/name_f] - White Wave.
[name_f]Ula[/name_f] - Sea [name_f]Jewel[/name_f].
[name_f]Morgana[/name_f]/[name_f]Morgane[/name_f]/[name_f]Morgaine[/name_f]/Morgayne/[name_u]Morgan[/name_u]/Morcan - Dweller of the Sea.
[name_f]Ebba[/name_f] - Flowing [name_m]Tide[/name_m].
[name_f]Orabel[/name_f]/[name_f]Orabelle[/name_f]/[name_f]Orabella[/name_f] - Beautiful Seacoast.
[name_f]Kaia[/name_f] -The Sea.
[name_f]Talia[/name_f] - Dew of [name_f]Heaven[/name_f].
Marisabel - Of the Beautiful Sea.
Malila - Fast [name_u]Salmon[/name_u] Swimming Up a Rippling Stream.
Zhaleh/Jaleh - Dew; [name_u]Rain[/name_u].
[name_f]Anahita[/name_f] - Persian [name_f]Goddess[/name_f] of Water.
[name_f]Cora[/name_f] - Seething Pool.
[name_f]Vanora[/name_f] - White Wave.
[name_u]Ara[/name_u] - Brings [name_u]Rain[/name_u].
[name_f]Mira[/name_f] - Water.
[name_u]Hali[/name_u]/[name_u]Halle[/name_u] - Sea.
[name_f]Naia[/name_f] - Wave.
Various deities relating to water:
Amphitrite - Posieidon’s Wife; Greek Sea [name_f]Goddess[/name_f].
Belisama - Celtics [name_f]Goddess[/name_f] of [name_m]Rivers[/name_m] and Streams.
Acionna -Celtics Sea [name_f]Goddess[/name_f].
[name_f]Electra[/name_f] - Greek Oceanid.
[name_f]Sirena[/name_f]/[name_f]Syrena[/name_f] - Filipino Mermaids.
[name_f]Saga[/name_f] - Norse Waterfall [name_f]Goddess[/name_f].
Greek Nymphs:
Nomia
Cleodora/Kelodora
[name_f]Melania[/name_f]
Castalia
Caliadne
[name_f]Moria[/name_f]
Lilaea
[name_f]Lara[/name_f]
Amatheia
[name_f]Thaleia[/name_f]
Pherusa
[name_f]Nerea[/name_f]
[name_u]Dione[/name_u]
[name_u]Calypso[/name_u]
Deira
Europa
[name_f]Eudora[/name_f]
[name_f]Ianthe[/name_f]
[name_f]Melia[/name_f]
[name_f]Nephele[/name_f]
[name_f]Xanthe[/name_f]
Rhanis
Pleione
Perseis/Priseis
[name_f]Anemone[/name_f]
[name_f]Halia[/name_f]
Ianessa
Iaira
Names that sound like Mermaid names:
[name_f]Venus[/name_f]
[name_u]Waverly[/name_u]
[name_f]Alaina[/name_f]/[name_f]Alana[/name_f]/[name_f]Alanis[/name_f]
[name_f]Adriana[/name_f]/[name_u]Adria[/name_u]
[name_f]Avalon[/name_f]
[name_f]Brisa[/name_f]
Silena
[name_f]Felicity[/name_f]
[name_f]Calista[/name_f]/[name_f]Callisto[/name_f]
[name_f]Sana[/name_f]
Sephima
[name_f]Seraphina[/name_f]
[name_f]Coralia[/name_f]
[name_f]Diana[/name_f]
[name_f]Shellina[/name_f]
Sereia
Nebulia
Euadne
[name_f]Lilla[/name_f]/[name_f]Lila[/name_f]
[name_f]Melody[/name_f]
[name_f]Genevra[/name_f]
Scylla
Hylla
[name_f]Raina[/name_f]/[name_f]Rayna[/name_f]/[name_f]Reina[/name_f]/[name_f]Reyna[/name_f]
[name_f]Rilla[/name_f]
[name_f]Lucia[/name_f]
Nireta
[name_f]Marnie[/name_f]
[name_f]Mavis[/name_f]
[name_f]Elora[/name_f]
[name_f]Natalia[/name_f]
[name_f]Lena[/name_f]
[name_f]Rena[/name_f]/[name_f]Rina[/name_f]
[name_f]Ria[/name_f]
[name_f]Rhianne[/name_f]
[name_f]Lianna[/name_f]/[name_f]Liana[/name_f]
[name_f]Nerice[/name_f]
Talora
[name_f]Sara[/name_f]
[name_f]Zahra[/name_f]
Lira
[name_f]Taura[/name_f]/Tauriel
[name_u]Laney[/name_u]/[name_f]Lainey[/name_f]
[name_f]Leah[/name_f]/[name_f]Lia[/name_f]
[name_f]Evaine[/name_f]/[name_f]Yvaine[/name_f]
Edilean
WOW!!! Sooooo many great names 
Thanx to everyone that posted…will be sure to update my signature with a few gems listed on this thread no doubt, merci beaucoup xx
Haha Btw, I love [name_u]Ariel[/name_u] too…[name_f]Cordelia[/name_f] and [name_f]Kira[/name_f]/ [name_f]Kara[/name_f]/ [name_f]Cara[/name_f] are nice too
Yes, it’s a lovely name…I think it’s okay for a girl too
Thanx for everyone’s wonderful suggestions xx
I love…
[name_u]Ariel[/name_u]
[name_f]Araluen[/name_f]
[name_f]Moselle[/name_f]
Brizo
[name_f]Delphine[/name_f]
[name_f]Coral[/name_f]
[name_f]Saga[/name_f]
Morgayne
[name_f]Kira[/name_f]/ [name_f]Kara[/name_f]/ [name_f]Cara[/name_f]
[name_f]Una[/name_f]
[name_u]Meredith[/name_u]
[name_f]Yvaine[/name_f]
Tauriel
[name_f]Syrena[/name_f]
[name_f]Oceane[/name_f]/a
[name_f]Pacifica[/name_f]
[name_u]Calypso[/name_u]
[name_f]Nerissa[/name_f]
Tethys
Coventina
xx
Lots of good suggestions. I’ll add [name_u]Chelsea[/name_u] to the list.
A few water related word names:
[name_f]Aqua[/name_f]
[name_u]Brook[/name_u]
[name_f]Coral[/name_f]
[name_f]Delta[/name_f]
[name_f]Pearl[/name_f]
[name_u]Rain[/name_u]
[name_u]River[/name_u]
[name_u]Storm[/name_u]
[name_f]Tempest[/name_f]
A few in Latin:
Aquata - “of the water”
[name_f]Nebula[/name_f] - “misty”
Venilia - “of the sea and winds”
A few in Hebrew:
Adva - “rippling water”
[name_f]Dalis[/name_f]/[name_f]Dalit[/name_f] - “drawing water”
[name_u]Jordan[/name_u] - “flowing down”
Talora/Talori - “morning’s dew”
A few in Irish:
Assana - “waterfall”
Avonmora - "from the great river"
[name_u]Shannon[/name_u] - “wise river”
A few in [name_m]French[/name_m]:
[name_f]Chenelle[/name_f] - “canal, channel”
Fontanee - “fountain, spring”
[name_f]Riva[/name_f]/[name_f]Rive[/name_f] - “from the shore”
A few in English:
Edlen, [name_u]Edlin[/name_u], [name_f]Edlyn[/name_f] - “noble waterfall”
Irvette/Irvetta - “friend of the sea”
[name_u]Lindsey[/name_u] - “from the lime island”
[name_f]Rilletta[/name_f]/[name_f]Rillette[/name_f] - “stream”
[name_f]Tyna[/name_f]/[name_f]Tyne[/name_f] - “river”
A few others:
Aspara - “moves in rainclouds”, Sanskrit
[name_f]Cari[/name_f] - “flows like water”, Turkish
Ersa - “dew”, Greek
[name_m]Iara[/name_m] - “water lady”, Brazilian
[name_f]Lin[/name_f], [name_u]Lyn[/name_u], [name_u]Lynn[/name_u], [name_f]Lynna[/name_f], [name_f]Lynne[/name_f] - “a cascade”, Anglo-[name_m]Saxon[/name_m]
[name_f]Laguna[/name_f] - “pool, pond”, Spanish
[name_f]Marisol[/name_f] - “sea and sun”, Spanish
[name_f]Marna[/name_f] - “the sea”, Scandinavian
Masika - “born during rain”, Egyptian
[name_f]Nadia[/name_f] - “having dew on the surface”, Arabic
You’ve already got a pretty long list so I’ll just throw in a few of my favourites!
(Celtic)Coventina-Water [name_f]Goddess[/name_f]
(Celtic)[name_f]Morgana[/name_f]/[name_u]Morgan[/name_u]-Dweller of the sea
(Celtic)[name_f]Ula[/name_f]- Sea [name_f]Jewel[/name_f]
(English)[name_u]Brooke[/name_u]/[name_u]Brooklyn[/name_u]-Water;Stream
(Turkish)[name_f]Cari[/name_f]-Flows like water
(Latin)Marissabel-Of the beautiful Sea
(Latin)[name_f]Marine[/name_f]/Marinella/Marinelle-Of the Sea
(Japanese)Umino-Child of the Sea
[name_f]Odessa[/name_f] (from Odyssey)