Military term for artillery units deployed in the field, as opposed to fortress or coastal artillery. Can refer to the branch, its personnel, or the guns themselves.
He went to the battlefield as a field artillery officer.
The field artillery shelled the enemy position.
野戦 means 'field operations' or 'field battle' in general; 野戦砲兵 specifically refers to the artillery branch or personnel in field operations.
砲兵 is the general term for artillerymen or the artillery branch; 野戦砲兵 narrows it to field artillery as opposed to other types.
Compound of 野戦 (field battle) + 砲兵 (artillery soldier). The term is a straightforward military designation with no obscure historical derivation.