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