adv. 25B6; adverb MOSTLY, for the most part, in the main, on the whole, largely, by and large, to a large extent, predominantly, chiefly, principally, primarily; generally, usually, typically, commonly, on average, as a rule, almost always.
MAINLY
Meaning of MAINLY in English
Concise Oxford thesaurus English vocabulary. Краткий оксфордский словарь английского языка тезаурус. 2012