Synonyms

mainly

American

[meyn-lee] / ˈmeɪn li /

adverb

chiefly; principally; for the most part; in the main; to the greatest extent.

Our success was due mainly to your efforts. The audience consisted mainly of students.
Obsolete. greatly; mightily; abundantly.

mainly British

/ ˈmeɪnlɪ /

adverb

for the most part; to the greatest extent; principally
obsolete strongly; very much

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of mainly

First recorded in 1225–75, mainly is from the Middle English word maynliche, maynly. See main ¹, -ly

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Heuristics is the fancy term for the human readiness to shove phenomena into categories into which they don’t quite fit, mainly to economize on mental effort.

From The Wall Street Journal • Apr. 14, 2026

This has led streaming services to look for ways to increase profitability, mainly by cutting costs and raising prices.

From MarketWatch • Apr. 13, 2026

On routine non-strike days, emergency departments are staffed mainly by early‑career doctors in training for specialist roles, who often order more tests and seek multiple layers of senior opinion.

From BBC • Apr. 13, 2026

"For many years, lifespan was attributed mainly to non-genetic factors, fueling skepticism about genetic determinants of longevity."

From Science Daily • Apr. 13, 2026

Books of drawings produced in the early modern period are mainly intended to advertise an engineer’s skills, not to provide you with the information you would need to do the job yourself.

From "The Invention of Science" by David Wootton

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023