dog

[GEORGE THOMPSON]

My father used to use the expression "I've got to see a man about a
dog" to mean "I'm going to wander off for a few minutes to find a
saloon and have a beer."  (Mother's translation.  Perhaps a full and
accurate decoding would have been: "I'm going to find a place where I
can take a leak, but I won't settle for any men's room that's not in
a saloon, and before I leave the saloon I will replenish my bladder
with a beer.)  I don't ever recall an occasion when he actually came
back with a dog.  That used to puzzle me.  In any event, my mother
and I were to stay where we were until he rejoined us.

RHHDAS finds the expression in the OED from 1867, and in the US from
1895.

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