Unusually competent, suppressing Right with singular argument (11)
I believe the answer is:
contretemps
'argument' is the definition.
(I've seen this before)
'unusually competent suppressing right with singular' is the wordplay.
'unusually' indicates an anagram.
'suppressing' says to put letters next to each other (in a down clue, some letters go on top of others).
'right' becomes 'r' (common abbreviation).
'with singular' becomes 's' (abbreviation sometimes used in dictionaries. I am not sure about the 'with' bit.).
'competent'+'r'='competentr'
'competentr' anagrammed gives 'contretemp'.
'contretemp'+'s'='CONTRETEMPS'
Can you help me to learn more?
(Other definitions for contretemps that I've seen before include "Unexpected mishap" , "Awkward occurrence or situation" , "Unexpected embarrassment" , "Prescott men (anag) - awkward moment" , "Minor disagreement" .)