Swash" src="http://typographydeconstructed.com/wp-content/uploads/2010/12/swash-white.gif" alt="Swash" width="190" height="190" />A flourish addition replacing a terminal or serif.

Some of the characters in ligatures were called swash characters, even though they did not protrude to the space on either side of the piece of type, such as the tail of a capital "Q" passing under its succeeding "u". Similarly the tail of a swash "g" would extend to the left beneath a number of preceding letters limited by the set of ligatures the typographer chose for the set.

mw Reference

An extended flourish on a printed character.