Definition of "Pill" :

noun: a dose of medicine in the form of a small pellet

noun: something that resembles a tablet of medicine in shape or size

noun: a contraceptive in the form of a pill containing estrogen and progestin to inhibit ovulation and so prevent conception

noun: something unpleasant or offensive that must be tolerated or endured

"His competitor's success was a bitter pill to take."

noun: a unpleasant or tiresome person