adverb Of a person or thing being the driving force influencing the outcome of an event; chiefly; certainly for the most part. .mw-parser-output .defdate{font-size:smaller}
adverb Forcefully, vigorously.
adverb Of the production of a sound: loudly, powerfully.
adverb To a great degree; very much.
adverb ↑ “mainly”, in Collins English Dictionary, 2011–present.
adverb ↑ “driving force”, in Collins English Dictionary, 2011–present.