Lethal

adj. fatal, deadly, causing death; very harmful, dangerous

Lethal is something that is capable of causing death to a living being. For example, a Lethal injection.It may also refer to:A Lethal gene, a gene which produces an organism which dies before reproducingLeigh Matthews, Australian rules footballer frequently referred to as "Lethal" or "Lethal Leigh"Lethal (film), a 2005 B-movie starring Heather Marie Marsden and Lorenzo LamasLethal is an Australian record company
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Adjective
1. of an instrument of certain death; "deadly poisons"; "lethal weapon"; "a lethal injection"
(synonym) deadly
(similar) fatal

(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 in the ethereal salt of lauric acid.
  

(a.)
Deadly; mortal; fatal.
  

Deadly.