ETYMOLOGY
from im- + Latin potare (to drink)
EXAMPLE
“…I never drunk or saw any usquebah since I came into Ireland, though I have bin at many tables and civilly used in a sober way without impoting: if any thing material doth happen in my concerns, I will send you word…”
From: Life and Letters of George Berkeley
From ye Court of Ireland, October 6, [1721]
– Alexander Campbell Fraser
Lexicophilia 