meter-long

The compound adjective 'meter-long' is a modern English formation that transparently combines two distinct measurement concepts. The first element, 'meter', entered English via French in the late 18th century, tracing back to the Greek metron, meaning 'measure', which itself derives from the Proto-Indo-European root me- (to measure). The second element, 'long', is a native English word from Old English lang, originating from the Proto-Germanic langaz and ultimately from the PIE root dlongʰo- (long). The compound's logic is purely descriptive, following a common English pattern (e.g., 'foot-long', 'mile-long') where a noun denoting a unit of linear measure is hyphenated with 'long' to create an adjective meaning 'having that specific length'. This formation illustrates how English readily creates precise technical descriptors by combining inherited and borrowed lexical elements.

Structure: meter (unit of length) + long (having length) - meter: From French mètre, from Greek metron (measure). In this compound, it functions as a noun specifying the unit of measurement. - long: From Old English lang, long (having great linear extent, lasting a considerable time). In this compound, it functions as an adjective meaning 'having length'.