lepton Definition

lepton¹
noun leptons

1. Any of various subatomic particles, including electrons, muons and tau particles, that only participate in weak interactions with other particles.
2. Formerly used to refer to any light particle, eg an electron, as opposed to a heavy one.

Derivative: leptonic
adj

Opposite of baryon.

Etymology: 1940s: from Greek leptos small or thin.

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lepton²
noun

lepta
1. A modern Greek coin worth 1/100th of a drachma.

Etymology: 18c: from Greek leptos to make slender.