As nouns the difference between calendar and poop
is that
calendar is any system by which time is divided into days, weeks, months, and years while
poop is the stern of a ship or
poop can be (often|childish) excrement or
poop can be a set of data or general information, written or spoken, usually concerning machinery or a process or
poop can be a slothful person.
As verbs the difference between calendar and poop
is that
calendar is (legal) to set a date for a proceeding in court, usually done by a judge at a calendar call while
poop is to break seawater with the
poop of a vessel, especially the poop deck or
poop can be (obsolete|intransitive) to make a short blast on a horn or
poop can be to tire, exhaust often used with
out .