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Medical Dictionary


noun \ˈfāz\

Medical Definition of PHASE

:  a particular appearance or state in a regularly recurring cycle of changes
:  a distinguishable part in a course, development, or cycle <the early phases of a disease>
:  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
:  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
:  an individual or subgroup distinguishably different in appearance or behavior from the norm of the group to which it belongs; also :  the distinguishing peculiarity
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