Definition of phase
1 : a particular appearance or state in a regularly recurring cycle of changes <phases of the moon>
2 a : a distinguishable part in a course, development, or cycle <the early phases of her career> b : an aspect or part (as of a problem) under consideration
3 : the point or stage in a period of uniform circular motion, harmonic motion, or the periodic changes of any magnitude varying according to a simple harmonic law to which the rotation, oscillation, or variation has advanced from its standard position or assumed instant of starting
4 : a homogeneous, physically distinct, and mechanically separable portion of matter present in a nonhomogeneous physicochemical system
5 : an individual or subgroup distinguishably different in appearance or behavior from the norm of the group to which it belongs; also : the distinguishing peculiarity
phasicplay \ˈfā-zik\ adjective
: in a synchronized or correlated manner
out of phase
: in an unsynchronized manner : not in correlation
Examples of phase in a sentence
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.
He has been throwing tantrums a lot, but the doctor says it's just a phase.
a calendar based on the phases of the moon
Origin and Etymology of phase
New Latin phasis, from Greek, appearance of a star, phase of the moon, from phainein to show (middle voice, to appear) — more at fancy
First Known Use: circa 1750
Definition of phase
1 : to adjust so as to be in a synchronized condition
2 : to conduct or carry out by planned phases
3 : to introduce in stages —usually used with in <phase in new models>
First Known Use of phase
PHASE Defined for English Language Learners
Definition of phase for English Language Learners
: a part or step in a process : one part in a series of related events or actions
: a short period of time during which a person behaves in a particular way or likes a particular thing
: the shape of the part of the moon that is visible at different times during a month
PHASE Defined for Kids
Definition of phase for Students
1 : a step or part in a series of events or actions : stage <I have completed the first phase of my training.>
2 : the way that the moon or a planet looks to the eye at any time in its series of changes with respect to how it shines <The new moon and the full moon are two phases of the moon.>
Medical Definition of phase
1: a particular appearance or state in a regularly recurring cycle of changes
2: a distinguishable part in a course, development, or cycle <the early phases of a disease>
3: a point or stage in the period of a periodic motion or process (as a light wave or a vibration) in relation to an arbitrary reference or starting point in the period
4: a homogeneous, physically distinct, and mechanically separable portion of matter present in a nonhomogeneous physicochemical system; especially : one of the fundamental states of matter usually considered to include the solid, liquid, and gaseous forms
5: an individual or subgroup distinguishably different in appearance or behavior from the norm of the group to which it belongs; also : the distinguishing peculiarity
Seen and Heard
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