A shoulder-fired missile, shoulder-launched missile or man-portable missile is a projectile

Projectile

A projectile is any object projected into space by the exertion of a force. Although a thrown baseball is technically a projectile too, the term more commonly refers to a weapon....

 fired at a target

Targeting (warfare)

Targeting is the process used to select objects or installations to be attacked, taken, or destroyed in warfare.Technologically advanced countries can generally select their targets in such a way as to minimize collateral damage and civilian casualties. This can fall by the wayside, however, during...

, small enough to be carried by a single person, and fired while held on one's shoulder

Shoulder

The human shoulder is made up of three bones: the clavicle , the scapula , and the humerus as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder make up the shoulder joints. The major joint of the shoulder is the glenohumeral joint, which...

. The word missile in this context is used in its original broad sense which encompasses all guided missiles and unguided rockets.
There are two kinds of shoulder launched weapons. The first is the recoilless gun, which is essentially an open tube.