(rare) Hot.

A situation has reached a point of great commotion, energy, or activity.

Alternative form of in heat

(military) Acronym of high explosive antitank: a munition using a high explosive shaped charge to breach armour.

Archaic spelling of heat.

Archaic spelling of heat.

A system that raises the temperature of a room or building. Compare heater. / The act of making something hot.

Causing heat.

present participle of heat

(uncountable) Thermal energy. / (uncountable) The condition or quality of being hot. / (uncountable) An attribute of a spice that causes a burning sensation in the mouth.