
1) Above all 2) As a rule 3) Basically 4) By and large 5) Chiefly 6) Essentially 7) First and foremost 8) For the most part 9) Fundamentally 10) Generally 11) In essence 12) In general 13) In good part 14) In principal 15) In the main 16) Largely 17) Mostly 18) On the whole 19) Predominantly 20) Primarily
Found on
https://www.crosswordclues.com/clue/mainly

1) Above all 2) As a rule 3) By and large 4) Chiefly 5) Particularly 6) Primarily 7) Principally
Found on
https://www.crosswordclues.com/clue/mainly

• (adv.) Principally; chiefly. • (adv.) Very strongly; mightily; to a great degree.
Found on
http://thinkexist.com/dictionary/meaning/mainly/
Main'ly adverb [ From
main strong. See
Main strength.] Very strongly; mightily; to a great degree. [ Obsolete]
Bacon. Shak. Found on
http://www.encyclo.co.uk/webster/M/9
No exact match found.