long

At its heart, long describes something stretched out—across a road, a piece of wood, or a span of time. It came through Middle English long, lang and Old English lang, from Proto-West Germanic lang, Proto-Germanic langaz, and ultimately the Proto-Indo-European form dlongʰos, meaning “long.” English’s shift from a to o before certain consonant clusters helps explain the modern spelling; the o may also have been reinforced by Old French long, from Latin longus, a related form. The basic spatial sense readily extends to duration: a long journey and a long wait share the image of distance, one measured in space and the other in time.