1570s, "affecting inward feelings," from French viscéral and directly from Medieval Latin visceralis "internal," from Latin viscera, plural of viscus "internal organ, inner parts of the body," of unknown origin. The bowels were regarded as the seat of emotion. The figurative sense vanished after 1640 and the literal sense is first recorded in 1794. The figurative sense was revived 1940s in arts criticism.

word-forming element meaning "inside, within, internal," from Greek endon "in, within" (from PIE *en-do-, extended form of root *en "in").

late 15c., "interior, inward, internal," from Old French intrinsèque "inner" (14c.), from Medieval Latin intrinsecus "interior, internal," from Latin intrinsecus (adv.) "inwardly, on the inside," from intra "within" (see intra-) + secus "along, alongside," from PIE *sekw-os- "following," suffixed form of root *sekw- (1) "to follow."

The form in English was conformed to words in -ic by 18c. Meaning "belonging to the nature of a thing" is from 1640s. Related: Intrinsical; intrinsically.

indicating the sound of a muffled internal combustion engine, 1904, imitative. Applied to various engines or objects which make such a sound.