Apogee Kick Motor
"Typically a solid rocket motor that "kicks" a payload from its initial launch trajectory into its final operating orbit." (McDowel 1997)
Sources
McDowel, Jonathan. 1997. "Kick In The Apogee - 40 Years Of Upper Stage Applications For Solid Rocket Motors, 1957-1997". 33Rd Joint Propulsion Conference And Exhibit. doi:10.2514/6.1997-3133.