One takes it to be chancy (4)
I believe the answer is:
risk
'one' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'takes it to be chancy' is the wordplay.
I cannot quite see how this works, but
'takes' could be 'is' (being is a kind of taking) and 'is' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for risk that I've seen before include "Assessment of potential dangers -- any silk saris (anag)" , "Gamble" , "Jeopardy" , "Possibility of bad outcome" , "dangerous thing" .)