Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “opt-in”

opt-in

noun [C or U] uk   /ˈɒpt.ɪn/ us    /ˈɑːpt-/
the fact of choosing to take part in an activity, arrangement, etc. rather than being forced to take part: The government operates an opt-in rather than an opt-out system, which means that permission must be sought on a case-by-case basis.
(Definition of opt-in noun from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of opt-in?
Add Cambridge dictionaries to your browser to your website

Definitions of “opt-in” in other dictionaries

Word of the Day

baby

a very young child, especially one that has not yet begun to walk or talk

Word of the Day

The way we move (Verbs for walking and running)

by Kate Woodford,
March 25, 2015
​​​ This week we’re looking at interesting ways to describe the way that people move. Most of the verbs that we’ll be considering describe how fast or slow people move. Others describe the attitude or state of mind of the person walking or running. Some describe both. Starting with verbs for walking slowly,

Read More 

stackin’ p

March 30, 2015
idiom slang earning a lot of money ‘That’s a very generous present.”Yeah, well, she’s stackin’ p, innit?’

Read More