-less /ləs/ BrE AmE suffix [in adjectives]
[ Language: Old English ; Origin: -leas , from leas 'lacking, false' ]
1 . without something:
I felt powerless.
a childless couple
tasteless food
2 . not doing or using something:
You’re too careless.
It’s perfectly harmless.
3 . not possible to treat or affect in a particular way:
on countless occasions
She’s tireless.