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in theory

ADJECTIVE
hypothetic
Synonyms
WEAK
abstract academic analytical as a premise assumed codified conjectural contingent formalistic formularized general hypothetical ideal idealized ideational ideological imaginative impractical in the abstract instanced intelle
ADJECTIVE
speculative
Synonyms
STRONGEST
analytical dangerous experimental hypothetical risky unproved unproven unsubstantiated
WEAK
abstract assumed conceptive dicey formularized hairy hazardous ideal idealized ideological iffy intellectual logical notional philosophical presumed uncertain
Antonyms
STRONGEST
proven safe
ADJECTIVE
theoretic
Synonyms
WEAK
abstract academic analytical as a premise assumed codified conjectural contingent formalistic formularized general hypothetic hypothetical ideal idealized ideational ideological imaginative impractical in the abstract instanced intellectual logical metaphysical notional on paper pedantic philosophical postulated presumed problematical pure quixotic speculative suppositional tentative transcendent transcendental unearthly unproved unsubstantiated vague
ADJECTIVE
theoretical
Synonyms
STRONGEST
abstract academic analytical imaginative intellectual logical metaphysical philosophical speculative vague
WEAK
as a premise assumed codified conjectural contingent formalistic formularized general ideal idealized ideational ideological impractical in the abstract instanced notional on paper pedantic postulated presumed problematical pure quixotic suppositional tentative transcendent transcendental unearthly unproved unsubstantiated
Antonyms
STRONGEST
concrete ignorant illogical material objective physical real simple
WEAK
certain definite factual proven

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.

These cases, in theory, could respond to early treatment and reduce certain cancer risk by up to 30%.

From The Wall Street Journal • May 4, 2026

While this makes sense in theory, it creates some issues.

From Slate • Apr. 24, 2026

I understood, in theory, the importance of a good knife.

From Salon • Apr. 21, 2026

So where there is good cybersecurity, this model would, in theory, hopefully be stopped.

From BBC • Apr. 17, 2026

As in Sudan, the emergence of a life form that could in theory have gone around the earth began with one infected person.

From "The Hot Zone" by Richard Preston