A unit of rhythm. Most phoneticians view the foot as having the structure SU0, where S = stressed syllable and U = unstressed syllable, that is a foot begins with a stressed syllable which is followed by zero or more unstressed syllables.

An example: ˈMary ˈhad a ˈlittle ˈlamb consists of four feet: |Mary|, |had a|, |little|, and |lamb|.

See also anacrusis.