Definition of "Realisation" :

noun: something that is made real or concrete

noun: making real or giving the appearance of reality

noun: the completion or enrichment of a piece of music left sparsely notated by a composer

noun: a sale in order to obtain money (as a sale of stock or a sale of the estate of a bankrupt person) or the money so obtained

noun: coming to understand something clearly and distinctly

noun: a musical composition that has been completed or enriched by someone other than the composer