optˈant noun

1. A person who opts
2. Someone who has exercised a power of choosing, esp his or her nationality

optative /optˈə-tiv or op-tāˈtiv/ adjective

1. Expressing a desire or wish
2. Denoting a mood of verbs that expresses a wish (grammar)

1. A mood of verbs, eg in Greek, expressing a wish
2. A verb in this mood

opˈtatively (or /op-tāˈ/) adverb

opˈter noun

optˈ-out noun

1. A decision or opportunity to opt out
2. A TV or radio programme broadcast by a regional station that has temporarily opted out of the main network transmission

opt in

To choose to take part

opt out

1. To choose not to take part (with of)
2. (of a school or hospital) to leave local-authority control