sergeant (sergeants plural )
1 n-count; n-title; n-voc A sergeant is a non-commissioned officer of middle rank in the army, marines, or air force.
A sergeant with a detail of four men came into view., ...Sergeant Black.
2 n-count; n-title; n-voc In the British police force, a sergeant is an officer with the next to lowest rank. In American police forces, a sergeant is an officer with the rank immediately below a captain. The unit headed by Sergeant Bell.
sergeant major (sergeant majors plural ), sergeant-major A sergeant major is a non-commissioned army or marine officer of the highest rank. n-count; n-title; n-voc
staff sergeant (staff sergeants plural ), Staff Sergeant A staff sergeant is someone who ranks just above sergeant in the British army or the United States army, marines, or air force. n-count; n-title
His father is a staff sergeant in the army., ...Staff Sergeant Robert Daily.