Room MW is a room toward the rear of the Bioweapon Research Center on the BOTTLE SHIP. Commander Adam Malkovich informs Samus Aran of a survivor in said room, wanting her to recover this person. The 'MW' presumably stands for 'Metroid Warriors', as this was where the Queen Metroid is kept and where most Metroid experiments presumably took place (although the Metroids actually lived in Sector Zero).