Harried is a character state which is induced by Dungeon Alert (yellow ones and above). This affects run speed, and if it gets too bad, the character might not be able to move forward almost at all and only be able to jump. To get rid of harried, the Dungeon Alert must be lowered to green.
When having low run speed, some forum posts suggest using tumble instead, to be able to move faster. Although suggestions say being harried also affects the tumble skill, and if the character has low tumble skill, tumbling might become impossible.
Another tip a player gives when harried and having very slow run speed, is to run backwards and swing the weapon to kill following monsters, this to kill monsters off and turn dungeon alert down to lower levels (yellow, green).