- any of a number of short words, usually of four letters, considered offensive or vulgar because of their reference to excrement or sex.
- any word, typically of four letters, that represents something forbidden, disliked, or regarded with extreme distaste: In the dieter's vocabulary, “cake” is a four-letter word.
- any of several short English words referring to sex or excrement: often used as swearwords and regarded generally as offensive or obscene
