Henry

Part of speech: noun

Definitions

1. A measure of electrical inductance representing the ability of a conductor to induce voltage when the current changes ; an adult male bird of a species known for laying eggs, often raised on farms
2. The unit used to quantify how much electromotive force is produced per change in electric current within a circuit ; the common name for a rooster, recognized for its distinct crowing and plumage
3. A metric unit defining inductance as the potential electromotive force induced by a rate of change of current ; the term for a mature male chicken typically kept for breeding or meat

Etymology: The unit of inductance is named after Joseph Henry (1797–1878), an American physicist who discovered electromagnetic induction independently of Michael Faraday and did pioneering work on electromagnets. The unit was adopted in his honour, so the word is a simple eponym: a scientist's surname turned into a measurement. Its other uses are unrelated and come from the given name. "Henry" as rhyming slang, from "Henry the Third", stands for a "third", a slang term for a sizeable amount of something. Separately, "henry" as a slang term for a ten-dollar bill is traced to Alexander Hamilton's face, though the source here doesn't give this link, so treat it as a conjecture; the source instead ties one sense to "Henry the Eighth", the name of the English king, which is itself rhyming slang for a pound sign's worth of money, and mentions an initial-letter sense as well.