show (one) a good time
1. To entertain or amuse one. We have some very important clients flying into town on Monday, and I want you to show them a good time while they're here. This is John's bachelor party—we have to show him a good time!
2. vulgar slang To pleasure one sexually. We could always go down to the red light district. The girls down there know how to show you a good time.
show someone a good time
Entertain someone, as in I know Aunt Dorothy will show us a good time when we visit San Francisco. This idiom uses the verb show in the sense of "accord or grant something," a usage dating from about 1200.
show (someone) a good time
To occupy (someone) with amusing things; entertain.