Military. the key group of officers and enlisted personnel necessary to establish and train a new military unit.
2.
a group of trained or otherwise qualified personnel capable of forming, training, or leading an expanded organization, as a religious or political faction, or a skilled work force: They hoped to form a cadre of veteran party members.
3.
(especially in Communist countries) a cell of trained and devoted workers.
4.
a member of a cadre; a person qualified to serve in a cadre.
Origin: 1905–10; < French: frame, border, bounds, cadre (metaphorically, the cadre being the framework into which temporary personnel are fit) < Italianquadro < Latinquadrum square; see quadri-
1830, from Fr. cadre, lit. "a frame of a picture" (16c.), so, "a detachment forming the skeleton of a regiment" (1851), from It. quadro, from L. quadrum "a square" (see quadrille). The communist sense is from 1930.