The compound "three-quarter" is a straightforward numerical construction in English, directly combining the numeral "three" with the noun "quarter," meaning a fourth part. The logic is purely arithmetic: three of four equal parts constitute three-fourths of a whole. This literal fractional meaning, dating to the late 16th century, was later applied descriptively to portraiture in the mid-19th century to specify a view between a full-length and a head-and-shoulders portrait, effectively showing about three-fourths of the subject's figure. The term exemplifies how English creates precise adjectival compounds from its native Germanic numeral system and a Latin-derived fractional noun.

Structure: three (numeral) + quarter (noun) - three: From Old English þrīe, þrēo, of Proto-Germanic origin; related to Latin trēs, Greek treis. Functions as a numeral root. - quarter: From Old French quartier, based on Latin quartus 'fourth', from quattuor 'four'. Functions as a noun denoting a fourth part.