What is the meaning of Spacer?

A person who works or lives in space.

An object inserted to hold a space open in a row of items, e.g. beads or printed type.

A bushing.

A forgetful person; one who spaces out.

A type of add-on device used by an asthmatic person to increase the effectiveness of a metered-dose inhaler.

An instrument for reversing a telegraphic current, especially in a marine cable, to increase the speed of transmission.

stroll, walk (wandering on foot; idle and leisurely walk)

Source: wiktionary.org