- For a guided electromagnetic wave, one of the possible manners or patterns of oscillation, transmission, or propagation. Such waves can propagate in one of three principal modes, which are as transverse electric waves, transverse magnetic waves, or transverse electromagnetic waves. Also called mode (3).
- In a transceiver, operation in which signals are sent. This contrasts with reception mode, in which signals are received. switching between the two modes may be automatic or manual.