Lexical Definition

‎θανάσιμος‎ thanásimos (than-as'-ee-mos) deadly ^G:A
from ‎θάνατος‎

deadly.

• fatal, i.e. poisonous

Abbott-Smith

* θανάσιμος, -ον (< θάνατος),
deadly: [18](/btb/interlinear/41%20-%20Mark/16/Mark.16.18.html)].†

Abbott-Smith References

Liddell-Scott-Jones

θανάσιμος [νᾰ], ον,

(θάνατος) deadly, fatal, [Refs 5th c.BC+]; θηρία θ., of poisonous reptiles, [Refs 2nd c.BC+], poisons, [NT+1st c.AD+] adverb -μως, τύπτειν to strike with deadly blow, [Refs 5th c.BC+]: neuter plural as adverb, ἀσπίδες -μα δάκνουσαι [Refs 1st c.BC+]

__2 belonging to death, θ. αἷμα the life-blood, [Refs 4th c.BC+]; μέλψασα θ. γόον having sung her death-song,[Refs 5th c.BC+]
__II of persons, near death, [Refs 5th c.BC+]; liable to the death-penalty, [Refs]
__II.2 dead, [Refs 5th c.BC+]

_{LSJ Scripture Refs: Mark.16.18}