An accent mark placed above variables to indicate shortness or smoothness, commonly used in linguistics and analysis.
Examples
Marking a short vowel sound in linguistics
\text{The pronunciation is } \breve{a} \text{ as in 'cat'}
Notation in music theory for short notes
\text{The rhythm pattern is } \breve{a}\breve{e}\breve{a}
Variable notation in mathematics
\text{Let } \breve{a} \text{ denote the short-time average of } a(t)