1.
If there is a ~ for something, it is very popular and fashionable.
Despite the ~ for so-called health teas, there is no evidence that they are any healthier...
= trend, fad
N-SING: oft N for n
2.
If something is in ~, is very popular and fashionable. If it comes into ~, it becomes very popular and fashionable.
Pale colours are much more in ~ than autumnal bronzes and coppers.
...the hippie-ethnic look which came into ~ in the late 60s.
PHRASE: v-link PHR, PHR after v