"small mammal," O.E. screawa "shrew-mouse," unknown outside English, perhaps from P.Gmc. *skreu- "to cut" (see shred
). Alternative O.E. word for it was scirfemus, from sceorfan "to gnaw." The meaning "peevish, malignant, clamorous, spiteful, vexatious, turbulent woman" [Johnson]
is late 14c., from earlier sense of "spiteful person" (male or female), mid-13c., traditionally said to derive from some supposed malignant influence of the animal, which was once believed to have a venomous bite and was held in superstitious dread. Shrewish "scolding" is from 1560s, originally "wicked, evil" (late 14c.).