Well today I will explain what "to be on fleek" means.
For anyone's eyebrows to be on "fleek" they have to be nicely lined up or nicely colored in.
Anyone's eyebrows can be on "fleek" as long as they look good.
Of course if you was to look up the meaning of "fleek" it wouldn't mean what it is used for now.
using "fleek" as a way to say something on someone looks "good" is definitely a trending way of using "fleek" therefore I believe that "fleek" will be out of style by next year (or who knows maybe later on this year).