# ## An encounter between opposing forces: an important battle in the Pacific campaign.Armed fighting; combat: wounded in battle. # A match between two combatants: trial by battle.A protracted controversy or struggle: won the battle of the budget.An intense competition: a battle of wits. #
'I'm at my Wits End' comes from 'Keep your wits about you' meaning to keep focus, concentration and strength. Therefore to be at your wits end is to have run out of wits, running out of focus, attention, patience and strength.