(historical, of garments) Having wide legs and reaching below the knees but higher than the ankles (not tied or closed at the knees).

Having one's arms open and apart / (idiomatic) cordial; friendly; welcoming

Disaster Management Open Platform for Emergency Networks. A system which provides interoperability interfaces for sharing of emergency-related information to vetted emergency management agencies.

A chess opening in which white begins by playing 1.c4, moving his queen bishop's pawn to the fourth rank.

(phonetics, of a vowel) pronounced with the tongue in a position approximately one-third of the way between an open and a close vowel

A romantic and/or sexual relationship in which the people involved are permitted or tolerated to be available to have additional simultaneous romantic and/or sexual relationships.

A marital relationship in which each partner agrees that the other partner may have sexual relations with other people as he or she sees fit.

plural of open relationship

A configuration of a mouth wherein the front top teeth are separated vertically from the front bottom teeth even while the back top teeth are resting directly upon the back bottom teeth.

plural of open bite