Sesquialtera ('one and a half') may refer to:
* Sesquialterum in mathematics, the ratio 3:2, a
superparticular ratio
In mathematics, a superparticular ratio, also called a superparticular number or epimoric ratio, is the ratio of two consecutive integer numbers.
More particularly, the ratio takes the form:
:\frac = 1 + \frac where is a positive integer.
Thu ...
* Sesquialtera or the equivalent Greek term
hemiola
In music, hemiola (also hemiolia) is the ratio 3:2. The equivalent Latin term is sesquialtera. In rhythm, ''hemiola'' refers to three beats of equal value in the time normally occupied by two beats. In pitch, ''hemiola'' refers to the interval of ...
, three in the time of two as variously used in music theory:
** Sesquialtera commonly describes a
tempo proportion in
mensural notation
Mensural notation is the musical notation system used for polyphony, polyphonic European vocal music from the late 13th century until the early 17th century. The term "mensural" refers to the ability of this system to describe precisely measur ...
** Hemiola is more common for the temporary substitution of a 2+2+2
musical meter
In music, metre (British spelling) or meter (American spelling) refers to regularly recurring patterns and accents such as bar (music), bars and Beat (music), beats. Unlike rhythm (music), rhythm, metric onsets are not necessarily sounded, but ar ...
for 3+3
*
Sesquialtera (organ stop), combining mutation ranks at 2' and 1', i.e. both 3:2 and 5:4 pitch ratios
*
''Sesquialtera'' (moth), a genus of moth in the family Geometridae
{{disambiguation