mainstream

n. prevailing trend or movement

adj. of the prevailing trend or movement

Mainstream is, generally, the common current of thought of the majority. It is a term most often applied in the arts (i.e., music, literature, and performance). This includes:something that is  ordinary or usual;something that is familiar to the masses;something that is available to the general public.
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Noun
1. the prevailing current of thought; "his thinking was in the American mainstream"
(hypernym) thought

n. mainstream, prevailing trend or movement

common, familiar, of the majority Smoking isn't as common now. It isn't a mainstream activity.