Hey I'm not one to grumble nor carp, but I thought LEADGIRL was as good as RILLED
(OK I was trying it on! Glad you're awake.)
I'm stumped again.
DETENSION-C
Following from CONTENDERS, there's only one possible word (that I'm aware of) that requires the addition of an A.
That would be CONTREDANSE
CONTREDANSE? please, you're making this up.
My next submission will be from the Zulu language. ;-)