What is "in hot water"

Hot \Hot\, a. [Compar. Hotter; superl. Hottest.] [OE. hot, hat, AS. h[=a]t; akin to OS. h[=e]t, D. heet, OHG. heiz, G. heiss, Icel. heitr, Sw. het, Dan. heed, hed; cf. Goth. heit[=o] fever, hais torch. Cf. Heat.]

1. Having much sensible heat; exciting the feeling of warmth in a great degree; very warm; -- opposed to cold, and exceeding warm in degree; as, a hot stove; hot water or air. ``A hotvenison pasty.''
   --Shak.

2. Characterized by heat, ardor, or animation; easily excited; firely; vehement; passionate; violent; eager.

   Achilles is impatient, hot, and revengeful.
   --Dryden.

   There was mouthing in hot haste.
   --Byron.

3. Lustful; lewd; lecherous.
   --Shak.

4. Acrid; biting; pungent; as, hot as mustard.

   Hot bed (Iron Manuf.), an iron platform in a rolling mill, on which hot bars, rails, etc., are laid to cool.

   Hot wall (Gardening), a wall provided with flues for the conducting of heat, to hasten the growth of fruit trees or the ripening of fruit.

   Hot well (Condensing Engines), a receptacle for the hot water drawn from the condenser by the air pump. This water is returned to the boiler, being drawn from the hot well by the feed pump.

   In hot water (Fig.), in trouble; in difficulties. [Colloq.]

   Syn: Burning; fiery; fervid; glowing; eager; animated; brisk; vehement; precipitate; violent; furious; ardent; fervent; impetuous; irascible; passionate; hasty; excitable.