As a Noun: 1. The fact that something is small in terms of importance or the time it lasts. 2. The fact that something lasts for only a short time. English = brevity. 3. The fact that something is of little importance; things which are unimportant. English = insignificance; trivia. As a Verb or Adjective: 1. To be very small in terms of the period of time something lasts or its significance. 2. To last for only a short period of time. English = (be) brief. 3. To be very small or unimportant. English = (be) trivial, (be) insignificant, (be) minor. As Modifier: 1. Used immediately next to a verb to mean that the action of the verb lasts only a short period of time. English = briefly. 2. Sometimes used at the beginning of a sentence to mean that you are about to say something in as few words or signs as possible. English = briefly.