​INSTALLATION, the action of installing or formally placing some one in occupation of an office or place. The med. Lat. installare meant literally “to place in a seat or stall” (stallum), and the word, as now, was particularly used of the ceremonial induction of an ecclesiastic, such as a canon or prebendary, to his stall in his cathedral choir. Similarly knights of an order of chivalry are ceremonially led to their stalls in the chapel of their order. The term is transferred to any formal establishment in office or position. From a French use of installer and installation, the word is frequently applied in a transferred sense to the fixing in position and making ready for use of a mechanical, particularly electrical, apparatus or plant.