(quantum mechanics, quantum electrodynamics) A small difference between the energy levels 2S_½ and 2P_½ of the hydrogen atom, not predicted by the Dirac equation, whose detection in the Lamb–Retherford experiment of 1947 foreshadowed the development of quantum electrodynamics (in which the discrepancy is explained to be an effect of the emission and re-absorption of virtual photons); such a difference between otherwise expectedly equal energy levels of hydrogen or any other type of atom.

plural of vegetable lamb

Chenopodium album, of the goosefoot family, sometimes used as a potherb / Any of several similar plants of genera Chenopodium and Atriplex.

(childish) A lamb or sheep. / Someone who is submissive, especially a husband or boyfriend.

(obsolete, humorous) A barrister / (obsolete, humorous) A customer at a bar (place that sells alcoholic drinks)

plural of baa-lamb

(countable) A lamb raised for slaughter wholly inside a building. / (uncountable) The meat of such a lamb.

plural of house lamb

corn salad or mâche, Valerianella locusta, a small plant of the family Caprifoliaceae whose leaves are used in salads.

(obsolete) An older version of the game of fox and geese.