There are 2 main definitions of opt out in English:

opt out1

Choose not to participate in or carry on with something: they had both opted out of the medical plan
More example sentences
  • Last spring, he opted out of football drills and chose instead to pitch for the USC baseball team, taking the hill in nine games.
  • A little-debated provision in the 1996 welfare reform law mandates a lifetime ban on welfare and food stamps for drug offenders, although New York is one of eight states that have opted out of the ban.
  • After the arrangements were made, Love opted out of the event altogether, as she reportedly ‘missed her plane’ from Los Angeles.
See parent entry: opt

Definition of opt out in:

There are 2 main definitions of opt out in English:

opt-out2

Syllabification: opt-out

noun

An instance of choosing not to participate in something: opt-outs from key parts of the treaty
More example sentences
  • But as the public backlash grows against the latest opt-outs, some doctors are studying in secret and choosing not to tell their colleagues and patients about the part-time nursing classes.
  • The Irish opt-out is therefore essentially meaningless because this tax will still hit people trying to travel into Ireland, including Irish people returning from abroad.
  • He said that if the Government successfully negotiated the defence opt-out, the leaders of his organisation would not campaign again against the treaty in a new referendum.

Definition of opt out in: