do somebody a/no service

do (someone) a service

To help or aid someone. Sharon did me a service by getting that jammed paper out of the printer.

See also: service

do (someone) no service

To do something that hinders or causes trouble for someone else. You do your kids no service by catering to their every whim.

See also: no, service

do somebody a/no ˈservice

(formal) do something that is helpful/not helpful to somebody: She was doing herself no service by remaining silent.

See also: no, service, somebody