in rhetoric, "repetition of the same word in a different sense" ("While we live, let us live"), 1650s, from Latinized form of Greek antanaklasis "reflection of light or sound," literally "a bending back against," from anti "against" (see anti-) + anaklan "to bend back."
1730, "dead person," now mostly as a term in U.S. law, from Latin decedentem, present participle of decedere "to die, to depart" (see decease (n.)).
1570s, from gasp (v.). Earliest attested use is in the phrase last gasp "final breath before dying." To gasp up the ghost "die" is attested from 1530s.
late 14c., "deadly, destructive to life; causing or threatening death" (of illness, poisons, wounds, etc.); also, of persons or the body, "doomed to die, subject to death;" from Old French mortel "destined to die; deserving of death" and directly from Latin mortalis "subject to death, mortal, of a mortal, human," from mors (genitive mortis) "death."
This is reconstructed to be from PIE *mr-o- "to die," *mr-to- "dead," *mr-ti- "death," all from PIE root *mer- "to rub away, harm" (also "to die" and forming words referring to death and to beings subject to death). The most widespread Indo-European root for "to die," it forms the common word for it except in Greek and Germanic.
"Subject to death," hence "human, of or pertaining to humans" (early 15c.). Also from late 14c. as "implacable, to be satisfied only by death" (of hatreds, enemies, etc.). Meaning "extreme, very great" is from late 14c. A mortal sin (early 15c., opposed to venial) is one that incurs the penalty of spiritual death.
late 14c., "of or manifesting life," from Latin vitalis "of or belonging to life," from vita "life," related to vivere "to live," from PIE root *gwei- "to live." The sense of "necessary or important" is from 1610s, via the notion of "essential to life" (late 15c.). Vital capacity recorded from 1852. Related: Vitally.
1530s, past-participle adjective from separate (v.). In reference to married couples deciding to live apart, from 1878.
c. 1600, "game park," from Latin vivarium "enclosure for live game, park, warren, preserve, fish pond," noun use of neuter singular of vivarius "pertaining to living creatures," from vivus "alive, living" (from PIE root *gwei- "to live"). Meaning "glass bowl for studying living creatures" is from 1853.