a head (taller/shorter); by a head
Used to describe a physical height difference roughly equal to the length of a head. Often appears with 高い/低い or 抜きん出る.
He is a head taller than his classmates.
The player stood a head above the crowd.
noticeable difference; cut above
Figurative use for a clear gap in ability, performance, or results, as if one competitor stands a head above the rest. Common in sports and competition contexts.
His ability is a cut above the other players.
This team leads the league by a noticeable margin.