Result of losing one's head in flirtation can be marriage (8)
I believe the answer is:
alliance
'marriage' is the definition.
(I've seen this before)
'result of losing one's head in flirtation can be' is the wordplay.
I cannot really understand how this works, but
an anagram of 'can' is 'anc' which is within the answer.
'be' could be 'lie' (lying is a kind of being) and 'lie' is found in the leftover letters.
'one' could be 'a' (a thing is one thing) and 'a' is found in the answer.
A single letter 'l' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for alliance that I've seen before include "Combination by treaty" , "League - treaty" , "A joining of forces" , "Coalition or union" , "match?" .)