What a thing is like

The third entry is plano, flat, and it is the one word on this list that English took in four separate times. Latin planus meant level, and each of its journeys north arrived with a different job to do. Through Old French it gave « plain », which named flat open country first and then whatever is clear and unadorned. It gave « plane », the flat surface of geometry and the carpenter’s tool that produces one. It gave « plan », by way of the drawing of a building seen from directly above — a flat picture of a thing that is not flat. Through Italian it gave « piano », the instrument whose full name promised soft and loud. And it sits inside « explain », which is ex- plus planare, to flatten a thing out until it can be read. Portuguese did none of that dividing. Plano is the adjective in uma superfície plana and the noun in um plano, a plan, and the sentence decides which one is meant. Meanwhile the ordinary English word for the quality, « flat », is not Latin at all: it came in from Norse.