noun
fang
FANG/fæŋ/
A long, sharp tooth used for biting or injecting venom.
The viper exposes a long curved fang in its open mouth.

Etymology
The underlying image is seizing or catching. The tooth sense probably developed from an Old English expression meaning “grasping-tooth,” and later extended to a serpent’s venom tooth.
In context
She holds up to 20 drops of venom per fang.