heater heater /ˈhiːtɝ/

noun

1. () Device that heats water or supplies warmth to a room  ( warmer , heater )
   device that heats water or supplies warmth to a room
    We installed a new gas heater to warm up our living room during winter
   We installed a new gas heater to warm up our living room during winter
   
   
2. (baseball) a pitch thrown with maximum velocity  ( bullet , heater , hummer , fastball , smoke )
   (baseball) a pitch thrown with maximum velocity
    He swung late on the fastball
   he swung late on the fastball
    He showed batters nothing but smoke
   he showed batters nothing but smoke