means The state or process of easing physical or mental tension, letting muscles loosen and the mind unwind from stress or effort.

from From Latin relaxare, 'to loosen or stretch out again' — built from re- ('back, again') plus laxare ('to loosen'), from laxus, 'loose, slack' (also the root of 'lax' and 'release'). The word arrived in English through Old French in the late medieval period, first describing the loosening of bodily tension before broadening to mean easing the mind.