To cause an increase in temperature of (an object or space); to cause to become hot (often with "up").
I'll heat up the water.
To become hotter.
There's a pot of soup heating on the stove.
To excite or make hot by action or emotion; to make feverish.
To excite ardour in; to rouse to action; to excite to excess; to inflame, as the passions.
To arouse, to excite (sexually).
The massage heated her up.
Very agitated, angry or impassioned.
a heated argument
(usually not comparable) Made warm or hot by some means.
a heated greenhouse / swimming pool / towel rail