Reckless, having an iridescent cocktail (10)
I believe the answer is:
indiscreet
'reckless' is the definition.
(I've seen this before)
'an iridescent cocktail' is the wordplay.
'cocktail' indicates anagramming the letters.
'iridescent' is an anagram of 'INDISCREET'.
'having' acts as a link.
(Other definitions for indiscreet that I've seen before include "Tactless" , "shameless" , "Too ready to tell secrets" , "Imprudent -- 10 across (anag)" , "Too ready to reveal secret things" .)