not capable of being distinguished or differentiated; "the two specimens are actually different from each other but the differences are almost indistinguishable"; "the twins were indistinguishable"; "a colorless person quite indistinguishable from the colorless mass of humanity"
impossible or difficult to perceive by the mind or senses; "an imperceptible drop in temperature"; "an imperceptible nod"; "color is unperceivable to the touch"
(astronomy) the particular appearance of a body's state of illumination (especially one of the recurring shapes of the part of Earth's moon that is illuminated by the sun); "the full phase of the moon"
(physical chemistry) a distinct state of matter in a system; matter that is identical in chemical composition and physical state and separated from other material by the phase boundary; "the reaction occurs in the liquid phase of the system"
a particular point in the time of a cycle; measured from some arbitrary zero and expressed as an angle
any distinct time period in a sequence of events; "we are in a transitional stage in which many former ideas must be revised or rejected"
adjust so as to be in a synchronized condition; "he phased the intake with the output of the machine"
not capable of being precisely or readily described; not easily put into words; "an indefinable feeling of terror"; "an abstract concept that seems indefinable"
defying expression or description; "indefinable yearnings"; "indescribable beauty"; "ineffable ecstasy"; "inexpressible anguish"; "unspeakable happiness"; "unutterable contempt"; "a thing of untellable splendor"
the impression that something is present; "he felt the presence of an evil force"
the immediate proximity of someone or something; "she blushed in his presence"; "he sensed the presence of danger"; "he was well behaved in front of company"
an invisible spiritual being felt to be nearby
the state of being present; current existence; "he tested for the presence of radon"
set up on the principle of collectivism or ownership and production by the workers involved usually under the supervision of a government; "collective farms"