adj · 1 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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Received-Pronunciation:/ˈɒptˌɪn/
Atlantic-Canada, General-American:/ˈɑptˌɪn/
Atlantic-Canada, General-American:/ˈɑpˌtɪn/
Mid-Atlantic, US:MarylandRecorded audio is listed in the source snapshot.
Australian:/ˈɔptˌɪn/
New-Zealand:[ˈɔ̟ptˌən]
rhymes with -ɒpt
1
adj
Meaning 1
The property of having to choose explicitly to join or permit something; a decision having the default option being exclusion or avoidance; used particularly with regard to mailing lists and advertising.
Definition source: English Wiktionary via Wiktextract
Usage: not-comparable
Examples
They set up an opt-in mailing list, so that those who wanted the notices could subscribe.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
History
Etymology
From opt + in.
Across languages
Translations
4 source translations are retained for this English entry.
German:
unter vorhergehender Einwilligung
— 1. The property of having to choose explicitly to join or permit something
German:
vorhergehende Einwilligung erfordernd
— 1. The property of having to choose explicitly to join or permit something
Polish:
uczestniczący
— 1. The property of having to choose explicitly to join or permit something
Spanish:
de adhesión
— 1. The property of having to choose explicitly to join or permit something