1 definition by Webster's New Brooklyn Dictionary

Upset, to the point of anger.
A combination of the terms "pissed off" and "miffed". Alternate spelling: mift off.
The pretty young lady was miffed off after her boyfriend sent her on a pointless trip to the grocery store (in a driving rainstorm, no less) to buy some wheat germ.
by Webster's New Brooklyn Dictionary September 17, 2004
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