Definify.com

Webster 1913 Edition

Adj.

[L.

mortifier

;

mors

mortis

, death +

ferre

to bring: cf. F.

mortifère

Bringing or producing death; deadly; destructive;

as, a

mortiferous

herb

Gov. of Tongue.

Adj.

[L. mortifer; mors, death, and fero, to bring.]

Bringing or producing death; deadly; fatal; destructive.

mortiferous ‎(comparative more mortiferous, superlative most mortiferous)

(now rare) Causing spiritual death. [from 16th c.]
- 2002, Colin Jones, The Great Nation, Penguin 2003, p. 140:
  Breton recruits were notorious for suffering from la nostalgie – a mortiferous form of homesickness.
Causing physical death; deadly, fatal, lethal. [from 16th c.]

deadly, fatal, lethal