In`fes*ta"tion (?), n. [L. infestatio: cf. F. infestation.] The act of infesting or state of being infested; molestation; vexation; annoyance. Bacon.

Free from the infestation of enemies.

• the presence of a large number of pest organisms in an area or field, on the surface of a host or anything that might contact a host, or in the soil.