LIGATURE.
1. A term in PRINTING for two or more joined letters cast in the same piece of type: æ in Cæsar; fl in florin; ffi in office. Early typefaces had many ligatures, imitating connected letters in handwriting, but few are retained in contemporary English printed alphabets. Vowel ligatures such as æ are now commonly replaced by open ae, even when transcribing LATIN, Latinized GREEK, and OLD ENGLISH: Caesar not Cæsar; Aelfric not Ælfric.

2. In PHONETICS, a mark like the slur in musical notation placed over or under a pair of symbols to show that they are spoken together: , and . Top ligature is favoured for letters with descenders, bottom ligature for letters with ascenders. Compare ASH, DIGRAPH.

li·ga·ture / ˈligəchər; -ˌchoŏr/ • n. 1. a thing used for tying or binding something tightly. ∎  a cord or thread used in surgery, esp. to tie up a bleeding artery.2. Mus. a slur or tie.3. Printing a character consisting of two or more joined letters, e.g., æ, fl. ∎  a stroke that joins adjacent letters in writing or printing.• v. [tr.] bind or connect with a ligature.

ligature.
1. The sign which in early notation (13th–16th cent.) combines several notes into one symbol:

2. The slur which in modern notation of vocal mus. shows that the 2 or more notes it affects are to be fitted to the same syllable, or, in instr. mus., that the notes are to be phrased together.

3. The tie or bind—a use of the word better avoided as unnecessary and confusing.

3. The adjustable metal band which in instr. of the cl. family secures the reed to the mouthpiece. Some clarinettists use string ligature.

See curved line, various uses of.

ligature (lig-ă-cher) n. any material – for example, nylon, silk, catgut, or wire – that is tied firmly round a blood vessel or duct to prevent bleeding, the passage of materials, etc.