incessant

/ɪnˈsɛsnt/

/ɪnˈsɛsɪnt/

Something incessant continues without interruption. When you're on a cross-country flight, it's tough to tolerate the incessant crying of a baby.

In Latin, cessare means "to stop," so when you add the negative prefix in-, you get a word meaning "never stopping." A near synonym is continual, but something incessant is more relentless; ceaseless is a closer synonym. It's rare to find incessant used in a positive way. Even incessant sunshine would grow boring.

Definitions of incessant

1. adjective

   uninterrupted in time and indefinitely long continuing
   “night and day we live with the incessant noise of the city”

   synonyms: ceaseless, constant, never-ending, perpetual, unabating, unceasing, unremitting

   continuous, uninterrupted

   continuing in time or space without interruption