do one's duty

Verb

do one's duty (third-person singular simple present does one's duty, present participle doing one's duty, simple past did one's duty, past participle done one's duty)

1. (euphemistic) Synonym of use the toilet: to urinate or defecate.
   • And when I was being toilet-trained as a very little boy, she'd always ask, "Have you done your duty?" That was the word for it.1996, Derrick Humphreys, John A. Munro, The making of a grey panther: the Derrick Humphreys story, page 8
   • If a society is incapable of that kind of trust, it is also incapable of freedom. But if one really believes that only productivity can create strength — that a human being, in other words, has to justify himself or herself by producing something — then maybe the psychoanalysts are right, and...2012, Alan Watts, Zen and the Beat Way

   Synonyms:

   use the toilet

2. Used other than figuratively or idiomatically: see do, duty.

   Synonyms:

   use the toilet