Source : Webster's Revised Unabridged Dictionary (1913)

Infest \In*fest"\, v. t. [imp. & p. p. {Infested}; p. pr. & vb.
   n. {Infesting}.] [L. infestare, fr. infestus disturbed,
   hostile, troublesome; in in, against + the root of defendere:
   cf. F. infester. See {Defend}.]
   To trouble greatly by numbers or by frequency of presence; to
   disturb; to annoy; to frequent and molest or harass; as,
   fleas infest dogs and cats; a sea infested with pirates.

         To poison vermin that infest his plants. --Cowper.

         These, said the genius, are envy, avarice,
         superstition, love, with the like cares and passions
         that infest human life.                  --Addison.

         And the cares, that infest the day, Shall fold their
         tents, like the Arabs, And as silently steal away.
                                                  --Longfellow.