transient

Something that is transient.

(physics) A transient phenomenon, especially an electric current; a very brief surge.

(acoustics) A relatively loud, non-repeating signal in an audio waveform that occurs very quickly, such as the attack of a snare drum.

A person who passes through a place for a short time; a traveller; a migrant worker.

A homeless person.

(programming, historical) A module that generally remains in memory only for a short time.

(Philippines) homestay