reservoir
UK[ˈrez.ə.vwɑː]US[ˈrez.ɚ.vwɑːr]
n
a natural or artificial lake where water is stored before it is taken by pipes to houses, factories, etc.
n
a large amount of something that is available to be used.
n
a part of a machine or an engine where a liquid is kept.
Morpheme Breakdown
re
serve
oir
re
back
serve
to keep, save, preserve
oir
Etymology
the word "reservoir" entered english in the 17th century from french, where it was formed from the verb "réserver" (to reserve, keep back). the french verb itself derives from latin "reservare", a compound of "re-" (back, again) and "servare" (to keep, save). the literal sense is "a place for keeping something back". the original and core meaning refers to a place where water is stored or kept back for future use. this concrete meaning logically extended to the modern abstract sense of any large reserve or supply of something, such as knowledge or talent.
Analysis
Structure: re + serve + oir
re: latin origin, a prefix meaning "back" or "again".
serve: from latin 'servare', meaning "to keep, save, preserve".
oir: french origin, a noun-forming suffix indicating a place or instrument for the action of the verb stem.
Examples
the heavy rains helped to refill the city's main reservoir.
she has a vast reservoir of patience when dealing with young children.
check the oil reservoir before starting the engine.