boundless

UK: /ˈbaʊndləs/ US: /ˈbaʊndlɪs/ ,(bound′lis)

WordReference Random House Learner's Dictionary of American English © 2026

bound•less /ˈbaʊndlɪs/   adj. 

1. having no bounds;
   unlimited:
   her boundless energy and enthusiasm.

WordReference Random House Unabridged Dictionary of American English © 2026

bound•less  (bound′lis), adj. 

1. having no bounds;
   infinite or vast;
   unlimited:
   His boundless energy amazed his friends.

• bound³ + -less 1585–95

bound′less•ly, adv. 
bound′less•ness, n. 
Synonyms

limitless, endless, unbounded, inexhaustible, illimitable.

Collins Concise English Dictionary © HarperCollins Publishers::

boundless / ˈbaʊndlɪs/ adjective

1. unlimited; vast: boundless energy

ˈboundlessly adverb