plural phases
1
: a part or step in a process : one part in a series of related events or actions
The project will be done in three phases.
He's in the final phase of treatment now.
The building project marks a new phase in the town's development.
These poems are from an early phase [=stage] in her career.
2
: a short period of time during which a person behaves in a particular way or likes a particular thing
He has been throwing tantrums a lot, but the doctor says it's just a phase.
She's going through a punk phase right now. [=she likes punk music and fashion at this point in her life]
3
: the shape of the part of the moon that is visible at different times during a month
a calendar based on the phases of the moon
4
British
: the state in which things work together with each other
—used in the phrases in phase or out of phase
Make sure the machine's wheels are moving in phase with each other.
The sound on this movie is out of phase. [=the sound does not match the images of the movie]
He seems to be out of phase [=(US) out of step] with the rest of the team.
Cite this Entry
“Phase.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/phase. Accessed 4 Apr. 2026.
Copy Citation
