I’m not entirely sure if I’ve got the right definition of trendy! I thought it was one of those newer names that are everywhere ([name]Ava[/name], [name]Addison[/name], [name]Avery[/name], [name]Kaitlyn[/name], etc) but, I googled the definition, and it was entirely different from what I thought! What do you define a trendy name as, and what are some examples? Thanks 
for me it’s popular names that have only been in the top 100 or so for the last 10-15 years.
names like [name]Elizabeth[/name], [name]Jacob[/name], [name]William[/name], [name]Sophie[/name] have all been in the top 100 for several years or were also popular 100 years ago so to me they are not trendy
names like [name]Kaitlyn[/name], [name]Ava[/name], [name]Madison[/name], [name]Aiden[/name], [name]Carter[/name] have only been popular recently.
I’d say it’s something that becomes insanely popular for a relatively short period of time, even if it’s an old name with ancient origins. And in 10-15 years it’ll start to be seen as dated and future generations will see it as an ‘old man name’ or ‘grandma name’.
In the early 90s, [name]Lauren[/name] & [name]Jessica[/name] and [name]Ryan[/name] & [name]Jordan[/name] became very popular very quickly and I’d say they were trendy. However, I reckon some names are exempt- [name]Charlotte[/name] & [name]James[/name] reached a similar levels of popularity but I don’t think they’ll ever be dated. Same goes for other classics like [name]William[/name], [name]Thomas[/name], [name]Elizabeth[/name] etc. Basically, I think ‘trendy’ is any name where you could easily guess the bearer’s date of birth to within a few years.
[name]Ava[/name] and [name]Aiden[/name] are very old names, they just came back and got popular.
To me it’s any name where it sounds like the parents were “trying too hard” - if that makes sense. Especially if there are Y’s and K’s and double letters in places that they don’t belong. Nothing wrong with the name [name]Michaela[/name], but when it becomes McKayllah, it becomes trendy to me. I also tend to lump traditionally masculine names used on girls in the trendy category. 50+ years ago, you would have been hard-pressed to find a female [name]Addison[/name] (I’m sure they were out there, but not in the numbers you see today). I don’t necessarily consider names that have existed for a long time but recently regained popularity as trendy, but they can be.
What’s the definition you found?
Trendy for me is when a name was somewhat uncommon and then suddenly became uber popular. Or the rise in popularity wasn’t gradual.
To me, trendy names are names that seem to come out of nowhere (and are usually made-up or don’t have a great deal of history behind them), are super popular overnight, then pretty much disappear after a few years. [name]Kennedy[/name] would be a good example. There was a period in the 90s when a bunch of little girls were named [name]Kennedy[/name] (or even worse, [name]Kennedi[/name]) and by 2000, no one was really naming their daughter that anymore.
[name]Kennedy[/name] has become way more popular in the last 10 years than it was in the 1990’s.
This.
It appears you are correct, though in my area, the name stopped being popular at least ten years ago. It still has a trendy feel though because it didn’t even chart until 1994 and it made its debut in the 500s. Then in one year it jumped up 300 spots, so iin two years you went from hearing no girls named [name]Kennedy[/name] to quite a few.
It’s definitely trendy! It’s twice as high in my state as the national ranking (which I find very surprising).
To me, a trendy name is one that has rocketed to popularity. Upswing [name]Baby[/name] Names wrote this great post on how to identify a future “fad name”.
To me a trendy name is a name that fits in with a group or type of names that is trending and is fairly popular or rising in popularity.
To me, Keneddi & [name]Bellamy[/name] are trendy, [name]Mason[/name] & [name]Fisher[/name] are trendy, [name]Ava[/name] & [name]Charlotte[/name] are trendy, even names like [name]Fiona[/name] & [name]Beatrice[/name] are trendy cause they’re on-trend (vintage/hipstery almost-classics) and probably on the rise (I would wager that they’ll both rise). [name]Evey[/name] name I listed (aside from Keneddi) are handsome names imo. So trendy doesn’t mean bad or awful or even necessarily too popular to me. I mean, I think that calf-high gladiator sandals are trendy at the moment, but that doesn’t mean that I know anyone who owns a pair! It means, timely to me. You could argue that a name like [name]Sofia[/name] is classic, but it is trendy as well imo.
I define trendy as a sharp rise in popularity and usually is only in the top 10/50/100 or whatever for a short period of time, like a decade, before dropping off. I also think of trendy names as ones which lead to similar sounding names also being used, like the Aidans or the -son ending names for girls.