Meaning of METRICAL UNIT

WordNet Dictionary
	Definition:		[n]  a group of 2 or 3 syllables forming the basic unit of poetic rhythm
	Synonyms:		foot, metrical foot
	See Also:		amphibrach, anapaest, anapest, beat, cadence, dactyl, dibrach, iamb, iambus, measure, meter, pyrrhic, spondee, trochee