-oire

From Latin -orium or -oria, also -oir. Cognate to English -ory and -or.

• IPA^(key): /waʁ/

-oire

1. A suffix used on verbs to form usually feminine words for objects or tools used to do something.

   ‎balancer + ‎-oire → ‎balançoire (“playground swing”)

   ‎bouillir + ‎-oire → ‎bouilloire (“teakettle”)

2. A suffix used on verbs (usually via the Latin supine form) to form masculine or feminine words for places where something is done.

   laboratoire (Latin laborare) — laboratory

   observatoire (observer) — observatory

3. A suffix used to form adjectives matched to nouns ending in -ation (or its variants) and derived from a Latin verb.

   ‎hallucination + ‎-oire → ‎hallucinatoire (“hallucinatory”)

   ‎giration + ‎-oire → ‎giratoire (“gyratory, roundabout”)

From Latin -oria.

-oire

1. indicates a tool or a device