defeat-n; 2 Senses

Sense Number 1: the outcome of a contest that is a loss

Commentary: DEFEAT[+event][+outcome][+loss][+of_contest]

Princeton's defeat at the nationals came as a surprise.
It is one of the most famous military defeats in history.
The patient's battle with cancer unfortunately ended in defeat.

WordNet 3.0 Sense Numbers: 1

Sense Number 2: feeling of being thwarted, frustrated in attaining a goal

Commentary: DEFEAT[+state][+emotional][+frustration][+thwarted]

Mary was put off by John's pervasive sense of defeat.
The photo captured the defeat in the faces of the war refugees.