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adj. Without stop or pause; constant. See Synonyms at continual.

adj. Without an end.

adj. Without stop or pause, incessant.

adj. Without pause or end; incessant.

ad. Without intermission or end.

Without a stop or pause; incessant; continual; that never stops or intermits; unending; never ceasing.

Endless; enduring forever: as, the ceaseless joys of heaven.

adj. uninterrupted in time and indefinitely long continuing

"He was quick and alert of movement, and his black eyes flashed from face to face in ceaseless scrutiny and challenge."

continuous    uninterrupted   

incessant    constant    endless   

incessant    unceasing    endless    unending    relentless    monotonous    fruitless    steady    frantic    intermittent