Definitions

sure

[shoor, shur] / ʃʊər, ʃɜr /

ADJECTIVE

certain, definite

Synonyms

STRONGEST

assured clear confident convinced positive

WEAK

abiding changeless constant convincing decided doubtless enduring firm fixed for a fact free from doubt genuine incontestable incontrovertible indisputable indubitable never-failing persuaded real satisfied set steadfast steady telling unchangeable unchanging uncompromising undeniable unequivocal unfailing unfaltering unqualified unquestionable unquestioning unshakable unshaken unvarying unwavering valid

Antonyms

STRONGEST

doubtful uncertain unsure

WEAK

doubted dubious humbled indefinite swerving unconfident unself-confident unsteady variable wavering wobbly

ADJECTIVE

physically stable

Synonyms

STRONGEST

fast safe strong

WEAK

firm fixed secure solid staunch steady

Antonyms

WEAK

doubted doubtful dubious humbled indefinite swerving uncertain unconfident unself-confident unsteady unsure variable wavering wobbly

ADJECTIVE

inevitable

Synonyms

STRONGEST

assured certain

WEAK

bound guaranteed indisputable ineluctable inerrant inescapable infallible irrevocable surefire unavoidable unerring unfailing

Antonyms

STRONGEST

doubtful doubting hesitant uncertain

WEAK

doubted dubious humbled indefinite swerving unconfident unself-confident unsteady unsure variable wavering wobbly

ADJECTIVE

self-confident

Synonyms

STRONGEST

assured certain confident decisive positive

WEAK

arrogant composed decided self-assured self-possessed

Antonyms

STRONGEST

doubtful doubting hesitant indefinite uncertain unsure

WEAK

doubted dubious humbled swerving unconfident unself-confident unsteady variable wavering wobbly

Usage

What are other ways to say sure? Sure, the simplest and most general of a group of adjectives indicating full belief and trust that something is true, expresses the mere absence of doubt. Certain suggests that there are definite reasons that have freed one from doubt. Confident emphasizes the strength of the belief or the certainty of expectation felt. Positive implies emphatic certainty, which may even become overconfidence or dogmatism.

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.

Guillermo Ochoa, who will be playing in his sixth World Cup with Mexico, is considered by many to be the ideal experienced goalkeeper to use during the opener, when nerves are sure to be high.

From Los Angeles Times • Jun. 11, 2026

Gather all the login credentials for your accounts, including banking and bills, as well as any other pertinent information someone might need to know to make sure everything is paid or transferred properly.

From MarketWatch • Jun. 10, 2026

For this World Cup, the plan is to make sure players get on with the game and save lost time this way.

From BBC • Jun. 10, 2026

To be sure, there is some concern that loyal Tesla investors would sell Tesla stock to buy SpaceX, which could put temporary downward pressure on the EV maker’s shares.

From Barron's • Jun. 10, 2026

I think I can climb out my window, but I’ve never tried before, so I’m not sure if it’ll work.

From "Split the Sky" by Marie Arnold

sure

Usage

Example Sentences

Related Words