Smart as many always are (6)
I believe the answer is:
clever
'smart' is the definition.
(similar in meaning)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for clever that I've seen before include "Deft, able, bright" , "Smart or quick at learning" , "Quick-witted, smart" , "brilliant" , "Quick and intelligent" .)