Definitions

mainspring

[meyn-spring] / ˈmeɪnˌsprɪŋ /

NOUN

bottom

Synonyms

STRONGEST

ground heart

STRONG

basis cause essence essentiality marrow origin pith principle quintessence root soul source stuff substance

WEAK

bottom line virtuality

Antonyms

STRONG

consequence effect end outcome outgrowth result

NOUN

cause

Synonyms

STRONGEST

element explanation matter motivation motive origin principle purpose root source

STRONG

account agency aim antecedent author basis beginning causation consideration creator determinant doer end foundation genesis ground grounds incitement inducement instigation leaven maker object occasion producer spring stimulation

WEAK

prime mover

Antonyms

STRONGEST

discouragement effect result

STRONG

conclusion finish neglect thoughtlessness

WEAK

consequence development fruit issue outcome outgrowth product

NOUN

cornerstone

Synonyms

STRONGEST

essential foundation keystone linchpin mainstay pillar

STRONG

anchor base

WEAK

key element main ingredient

NOUN

fountain

Synonyms

STRONGEST

geyser reservoir stream

STRONG

bubbler cause font fount gush inception inspiration jet lode mine origin play provenance provenience pump root spout spray spring well wellhead wellspring

Antonyms

STRONG

conclusion consequence effect end outcome outgrowth result

NOUN

keynote

Synonyms

STRONG

basis center core cornerstone criterion crux essence gist heart idea kernel keystone linchpin marrow measure motive nub pith principle root source spring standard substance

WEAK

basic idea central idea

Antonyms

STRONG

end exterior exteriority outside periphery result surface

NOUN

keynote/keystone

Synonyms

WEAK

basic idea basis center core cornerstone criterion crux gist heart idea kernel linchpin marrow measure motive nub pith principle root source spring standard substance

NOUN

motive

Synonyms

STRONGEST

aim cause consideration emotion feeling idea impulse influence intent intention motivation passion rationale

STRONG

antecedent basis design determinant drive end grounds incentive incitement inducement inspiration object occasion root spring spur stimulus thinking

Antonyms

STRONGEST

neglect thoughtlessness

STRONG

discouragement hindrance

WEAK

deterrent

NOUN

origin

Synonyms

STRONGEST

ancestor ancestry connection element influence motive provenance root source

STRONG

agent antecedent author base causality causation creator derivation determinant egg embryo fountain generator germ impulse inception inducement inspiration nucleus occasion parent parentage principle producer progenitor provenience roots seed spring stock well wellspring

WEAK

horse's mouth

Antonyms

STRONG

conclusion effect end ending result

WEAK

close completion consequence death destiny finale goal outcome outgrowth termination

NOUN

provenience

Synonyms

STRONG

agent ancestor ancestry antecedent author base beginning causality causation connection creator derivation determinant egg element embryo fount fountain fountainhead generator germ impulse inception inducement influence inspiration mother motive nucleus occasion parent parentage principle producer progenitor provenance root roots rootstock seed source spring stock well wellspring

WEAK

horse's mouth

Antonyms

STRONG

conclusion discouragement effect end ending finish hindrance result

NOUN

root

Synonyms

STRONGEST

essence foundation heart origin seed soul source stem stuff

STRONG

basis bedrock beginnings bottom cause center crux derivation essentiality footing fountain fountainhead fundamental germ ground groundwork inception infrastructure marrow motive nub nucleus occasion pith provenance provenience quick quintessence radicle radix reason rhizome seat substance substratum tuber underpinning well

WEAK

rock bottom starting point

Antonyms

STRONGEST

effect end result

STRONG

conclusion consequence exterior exteriority extra outgrowth outside trivia

WEAK

derivation derivative sprout

NOUN

rootstock

Synonyms

STRONG

agent ancestor ancestry antecedent author base beginning causality causation connection creator derivation determinant egg element embryo fount fountain fountainhead generator germ impulse inception inducement influence inspiration mother motive nucleus occasion parent parentage principle producer progenitor provenance provenience root roots seed source spring stock well wellspring

WEAK

horse's mouth

Antonyms

STRONG

conclusion discouragement effect end ending finish hindrance result

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.

The Fountain’s tradition of extending a wide communal embrace, welcoming underrepresented voices and addressing urgent social concerns, is clearly going to be a mainspring of Caldwell’s leadership.

From Los Angeles Times • Sep. 24, 2025

This was the mainspring of the anti-liberal revolt in the region.

From The Guardian • Oct. 24, 2019

That’s the mainspring tension of this six-month baseball thing.

From Washington Post • Aug. 14, 2019

Charlie chimes in with the spoken footnote that suggests the movie’s hidden mainspring:

From The New Yorker • Aug. 11, 2015

“It’s how my father taught me. If I don’t wind it consistently, it won’t keep time as well. And if I overwind it, the mainspring might break.”

From "The City Beautiful" by Aden Polydoros

mainspring

Example Sentences

Related Words