Bond is topless superhuman (5)
I believe the answer is:
ionic
'bond' is the definition.
(ionic bond is a kind of bond)
'topless superhuman' is the wordplay.
'topless' means to remove the first letter.
'superhuman' becomes 'bionic' (I've seen this in another clue).
'bionic' with its first letter removed is 'IONIC'.
'is' acts as a link.
(Other definitions for ionic that I've seen before include "Architectural order" , "Greek tongue" , "Support (a weight)" , "Classical style" , "classical Greek design" .)