Clue-answer notation is a notational system used to represent the inner workings (wordplay) of cryptic clues which often obviates the need for potentially lengthy verbal explanations.
Notation key Edit
Though many variants on the notation exist, the most frequently seen are detailed in the table below. Where multiple possibilities exist, the most common are listed first.
or ABC (rev.)
|ABC reversed. The (rev.) notation is most commonly used when the wordplay consists of a single reversal.|
|Letters abc removed, as in [c]OUNT to represent 'count' with c removed; the convention is to use lower case for the removed letters.|
|(ABC)||Letters placed inside others, as in C(AND)ID to mean 'and' inside 'cid'.|
|"ABC"||Homophone of ABC.|
|(ABC)*||Anagram of ABC.|
|A+B or A,B||A concatenated with B. Sometimes both notations are used together where ambiguities may arise.|
|aBcDeF||Alternate letters of ABCDEF (shorthand for [a]B[c]D[e]F).|
Consider the down clue
A message from the setter, hauled up with broken arm after heroin withdrawal (8)
yielding the answer TELEGRAM. The corresponding wordplay, having the prolix and possibly ambiguous explanation
THE next to LEG reversed next to an anagram of ARM, all with H (heroin) removed
could be concisely represented in clue-answer notation simply as T[h]E,GEL<=,(ARM)*.