Certain

Having or feeling no doubt or uncertainty; confident and assured

Synonyms

Sure

Antonyms

Uncertain

Examples

Felt certain of success

Was sure (or certain) she had seen it

Certain to occur; destined or inevitable

Synonyms

Sure

Antonyms

Uncertain

Examples

He was certain to fail

His fate is certain

In this life nothing is certain but death and taxes

He faced certain death

Exercising or taking care great enough to bring assurance

Synonyms

Sure

Similar to

Careful

Examples

Be certain to disconnect the iron when you are through

Reliable in operation or effect

Synonyms

Sure

Examples

A quick and certain remedy

Established irrevocably

Synonyms

Sealed

Definite but not specified or identified

Similar to

Definite

Examples

Set aside a certain sum each week

To a certain degree

Certain breeds do not make good pets

Certain members have not paid their dues

A certain popular teacher

A certain Mrs. Jones

Established beyond doubt or question; definitely known

Antonyms

Uncertain

Examples

What is certain is that every effect must have a cause

It is certain that they were on the bus

His fate is certain

The date for the invasion is certain