The story
From de Broglie + wavelength. Named for Louis de Broglie.
Etymology from Wiktionary, CC BY-SA 4.0.
de Broglie wavelength
Today it means: the wavelength, λ=h/p, associated with a beam of particles of momentum p. (h being Planck's constant.) The same formula gives the momentum of a photon or wavelength λ. Full definition →