To carry out (a process) in gradual stages. The company plans to phase the new software implementation over the next six months.
To introduce or withdraw something gradually or in stages. The government decided to phase out the old currency notes by the end of the year.
To adjust or synchronize the phase of (a waveform, signal, or alternating current) so that it is in the desired relative position. The technician phased the microphone signals to prevent feedback.