What does mostly mean?
Mostly is an adverb meaning that something is true in the greatest number of cases or forms the predominant part of a whole. It commonly replaces phrases such as “for the most part,” “in most cases,” and “usually.” For example, a statement that a group is “mostly retired” indicates that retirement is the prevailing characteristic, while acknowledging that not everyone belongs to that category. Mostly is widely used in everyday conversation, academic writing, journalism, and formal descriptions, although it may suggest that exceptions exist. It is also more precise than the informal “most” and can modify verbs, adjectives, or entire clauses: “The work mostly concerns local history,” or “The results were mostly unchanged.” Because it describes what is typical rather than what is absolute, mostly is especially useful when discussing general patterns, predominant characteristics, and approximate quantities.
adverbFor the most part or in the greatest number of cases; usually. It can also indicate that something is true in a predominant or nearly total part of a larger whole.
- For the most part; usually or predominantly.
- In the greatest or nearly the whole part of something.
"The audience was mostly composed of students and local residents."
"The project was mostly completed before the deadline."
"These days, I mostly work from home."
When you want to say “usually,” but with a touch more precision, reach for mostly.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does mostly come from?
Mostly was formed in the early 17th century by adding the suffix -ly to most, with the sense “for the most part” or “chiefly.” Most descends from Old English māst, meaning “greatest,” and is related to more; both have Germanic origins and cognates such as German meist and Dutch meest. The development of mostly therefore reflects the general English pattern of turning an adjective such as most into an adverb through the productive -ly suffix.
How mostly is actually used
Mostly is common in both formal and informal English. It often suggests that an exception exists, so it can be less absolute than “always” or “entirely.” In informal contexts, “mostly” may be shortened to “most,” though this can sound casual or slightly less precise.
Easily confused with mostly
Most means the greatest amount or number, while mostly means usually or predominantly.