virulency

vir=u=len=cy

WORDNET DICTIONARY

virulency(n = noun.attribute) virulence - extreme harmfulness (as the capacity of a microorganism to cause disease); "the virulence of the plague"

is a kind of harmfulness, injuriousness

Derived form adjective virulent₁

virulency(n = noun.attribute) virulence - extreme hostility; "the virulence of the malicious old man"

is a kind of hostility, ill will

Derived form adjective virulent₃

virulency, n. [Cf. F. virulence, L. virulentia an offensive odor, a stench.].

The quality or state of being virulent or venomous; poisonousness; malignancy. [1913 Webster]
Extreme bitterness or malignity of disposition. Barrow. [1913 Webster]
"The virulence of one declaimer, or the profundities and sublimities of the other." [1913 Webster]