stoop, stoup

Stoop or stoop means to bend over, or to lower oneself, literally or figuratively--
He had to stoop to get through the low doorway.
He wouldn't stoop to behavior like that.
Stoop may also mean a small raised platform or porch--
They sat on the stoop on warm nights.

Stoup or stoup ( rhymes with stoop ) means a drinking vessel or tankard--
He stopped at the inn each evening for a stoup of ale.
Stoup may also mean the quantity of liquid defined by the same drinking vessel or tankard--
A stoup was roughly equivalent to a pint.
Stoup also means a basin set into the wall of a church, used for holy water--
He dipped his fingers in the stoup and made the sign of the cross.

 Now that you know that, you can say--
"Some gave short measure of ale, but the publican wouldn't stoop to putting less than a stoup of ale in each stoup."