well there are quite a few antonyms for customary. You could use abnormal, different, or irregular.
average everyday ordinary typical expected run-of-the-mill commonplace unexceptional unremarkable usual familiar predictable common customary natural
It is a customary unit.
To the Adams Family, it isn't customary to leave a tip for the waiter.
yes it is customary
The antonym of the word 'synonym' is 'antonym'.
It is a customary unit.
customary
An antonym means "opposite". So an antonym for the word synonym is antonym.
Yes, customary is the correct spelling.
customary
it is in the us customary unit or else we wouldnt be learning about. there for it is in the us customary unit.
Customary law