late 15c., in alchemy, "transmutation by casting a powder on molten metal; 1550s in the cartographical sense "drawing of a map or chart according to scale," from Middle French projection, from Latin proiectionem (nominative proiectio), from past participle stem of proicere (see project (n.)). From 1590s as "action of projecting."
projection pro·jec·tion (prə-jěk'shən)
The act of projecting or the condition of being projected.
The attribution of one's own attitudes, feelings, or suppositions to others.
The attribution of one's own attitudes, feelings, or desires to someone or something as a naive or unconscious defense against anxiety or guilt.
The localization of visual impressions to a point in space relative to the person who is doing the viewing: straight ahead, right, left, above, or below.
Any of the systems of nerve fibers by which a group of nerve cells discharges its nerve impulses to one or more other cell groups.