unless

/ənˈlɛs/

except if

You won't pass the exam unless you study hard.

This means passing depends on studying hard.

formalinformal

Introduces an exception to a general statement or condition.

You can't enter the building unless you have a pass.

Entry is only allowed with a pass.

Unless you apologize, she won't forgive you.

Apologizing is the only way to gain forgiveness.

Often used to express a condition that must be met for something to happen.

Collocations

unless otherwise statedif no other information is givenunless youif you do not

if no other details are provided

Use 'unless' to express that something will only happen if a specific condition is met.

'Unless' is used to introduce the only condition under which a statement is not true.

From Middle English 'onles', from Old English 'onlæss' meaning 'except' + 'læss' meaning 'less'.

Often used in formal and informal contexts to introduce a condition that must be met for a statement to be true.

un-

not

prefix

-less

without

suffix

English Dictionary