D defs.my
Entry 2 senses · 2 variants Webster, 1913

Lethal

/(lĕth"ăl)/ · Leth·al · IPA /ˈliː.θəl/
01 n. One of the higher alcohols of the paraffine series obtained from spermaceti as a white crystalline solid. It is so called because it occurs…
  1. 1.
    One of the higher alcohols of the paraffine series obtained from spermaceti as a white crystalline solid. It is so called because it occurs in the ethereal salt of lauric acid.(Chem.)
02 a. Deadly; mortal; fatal.
  1. 1.
    Deadly; mortal; fatal.