The compound "three-shot" is a modern English formation combining the cardinal number "three" with the noun "shot." The word "three" has a deep Indo-European lineage, tracing back to the PIE root tréyes, which evolved into the Proto-Germanic þrīz and Old English þrīe. "Shot" originates from the Old English verb scēotan, meaning "to project, to launch," with its nominal form denoting the act or result of shooting. In contemporary usage, "shot" has broadened semantically to represent a single attempt, a turn in a game, or a small serving of alcohol. Thus, "three-shot" logically denotes a set of three such attempts, successes, or servings, its meaning fully transparent from the sum of its parts.

Structure: three (number) + shot (unit/attempt) - three: From Old English þrīe, þrēo, from Proto-Germanic þrīz, from Proto-Indo-European tréyes. Functions as a cardinal number. - shot: From Old English sc(e)ot, gesceot (act of shooting), related to scēotan (to shoot). In this compound, it functions as a noun meaning a single attempt, a turn, or a measure of liquor.