The term 'INSERT IN A TAPE RECORDER' can be summarized as the action of placing a CASSETTE into a tape recorder. A CASSETTE is an 8-letter word that refers to a magnetic tape sound recording format, which was popular in the 1970s and 1980s. It consists of two miniature spools, between which a magnetic tape is wound. The CASSETTE is inserted into a tape recorder, which then reads the magnetic tape and plays the audio stored on it.