Sicken

Definition:

(v. t.) To make sick; to disease.
(v. t.) To make qualmish; to nauseate; to disgust; as, to sicken the stomach.
(v. t.) To impair; to weaken.
(v. i.) To become sick; to fall into disease.
(v. i.) To be filled to disgust; to be disgusted or nauseated; to be filled with abhorrence or aversion; to be surfeited or satiated.
(v. i.) To become disgusting or tedious.
(v. i.) To become weak; to decay; to languish.

Compare sicken with other words:

sicken vs. sicker