Coin-tossing call (5)
'coin-tossing call' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for heads that I've seen before include "Obverse of a coin" , "Obverse result of coin-tossing" , "a 50-50 chance" , "School principals" , "Coin-tossing call" .)
'coin-tossing call' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for tails that I've seen before include "Gambler's choice" , "A possible fall of the pound" , "Ends" , "the back of bears - bulls too" , "Evening dress; coin toss call" .)