A moray is a type of eel (any type in the Muraenidae family).1 Mores are the shared habits or characteristics of a group. Mores is always plural. We could not find a corresponding singular noun in any of the dictionaries we checked (though in theory there’s no reason why it could not be used singularly). The word comes from Latin, where mores is plural for mos, which means custom.2
Examples
Usage of moray is easy, so we won’t provide any examples of moray used correctly. But, just for fun, here are a couple of examples of morays misused in place of mores:
He said that morays had changed since the Sixties and subsequent decades. [Telegraph]
Rigid social morays leave no room outside the box. [Seattle Times's Ed Cetera blog]
And here are a few examples of mores used well:
… Jobs fully embraced the hippie-dippie mores of his native Northern California: he dropped acid, smoked dope, lived in a commune … [Salon]
Ozon’s pointedly colourful depiction of the mores of mid-70s French society is mildly subversive fare … [Guardian]
Their job, as they saw it, was to protect minorities from the depredations of middle-class mores. [The Australian]
References
1. http://en.wikipedia.org/wiki/Moray_eel ^
2. http://www.oed.com/view/Entry/122201 ^
