one-ounce

The compound adjective 'one-ounce' is a transparent combination of the numeral 'one' and the unit of measure 'ounce'. The word 'one' traces back to Proto-Germanic 'ainaz', sharing a root with the Latin 'unus', both derived from the Proto-Indo-European 'óynos', meaning single or one. 'Ounce' has a more complex journey, originating from the Latin 'uncia', meaning a twelfth part, which itself may derive from the PIE root 'oynos' (one) via the concept of a single unit of a larger whole. The modern sense of 'ounce' as a specific unit of weight was standardized in the English system. When combined, the morphemes retain their literal meanings, creating a term that precisely denotes a weight of one ounce, often used figuratively to describe something very small or lightweight.

Structure: one (numeral) + ounce (unit of weight) - one: From Old English 'ān', meaning the number one. It functions as a numeral specifying a single unit. - ounce: From Old French 'unce', via Latin 'uncia' meaning a twelfth part (of a pound or foot). It functions as a noun denoting a unit of weight.