Are you sure it starts with cu? Maybe the c is off and the answer could be quad.
Try looking at the answers and see if something else could be changed to see if one of the following works:
Area
Rift
Quad
then
find
Pact
alfa
oath
emit
felt
hoax
A four letter word starting with the letter a is able.
pour
copy
A four letter word meaning not kosher is: tref