massless

From mass + -less.

• (US) IPA^(key): /ˈmæs.ləs/, /ˈmæs.lɪs/
• Rhymes: -æsləs

massless (not comparable)

1. Having no mass.

   The photon is a massless particle.

   • 2014, Mark A. Cunningham, Neoclassical Physics, page 241:

     On the other hand, Pauli had just proposed a massless, chargeless, colorless, flavorless particle whose sole reason for existence was to preserve the principle of momentum conservation.

• massive

• masslessness