multiplet noun. ['mʌltɪplǝt] E20.
[from MULTIPLE adjective + -ET¹, after doublet, triplet, etc.]
Physics.
1. A closely spaced group of related spectral lines in a spectrum; a group of related atomic states or energy levels with slightly different energies. E20.

2. A group of subatomic particles that differ only in charge. Also, a series of such groups, each characterized by a different value of hypercharge (or strangeness) but having the same spin and parity. M20.

[TahlilGaran] English Dictionary ▲