have a derry on (one)
To have negative, usually discriminatory, feelings toward one. Primarily heard in Australia, New Zealand. Grandpa has always had a derry on people from that side of town.
have a derry on someone
be prejudiced against someone. Australian & New Zealand This expression refers to the traditional song refrain derry down , and was a late 19th-century adaptation of have a down on (see down).
1948 David Ballantyne The Cunninghams She didn't like the Baptists though, had a derry on that crowd ever since Hilda took her to an evening service.