Rest

Rest has several different meanings. See:

rest (music), a pause in a piece of music.
rest (object), a support for a musket or billiards or snooker cue.
rest (physics), the relation between two observers.
rest as action, to relax, see leisure; compare recreation.
The reserves of the Bank of England.
In software engineering, REST is an acronym for Representational State Transfer.
ReST also refers to the markup language reStructuredText.
In chemistry a rest (abbreviated R) is a variable part of a molecule attached to a given core structure. See: Functional group and side chain.