hot water

baking hot

Very hot.

blood in the water

In a competitive situation, the exhibition of apparent weakness or vulnerability by one party, especially when this leads to a feeling of vulnerability or greater pressure to perform on the part of the weak party, or enhanced expectation of victory by the others.

blood is thicker than water

Family relations and loyalties are stronger than relationships with people who are not family members.

blow hot air

To engage in empty or exaggerated talk that lacks substance, credibility, or truth; to bluster.

blow hot and cold

To behave inconsistently; to vacillate or to waver, as between extremes of opinion or emotion.

blow out of the water

To trounce; to defeat thoroughly, as at a game or in battle.

boiling hot

Extremely hot (having a high temperature: of an object, the weather, a living creature).

carbonated water

Water that contains carbon dioxide dissolved in it under pressure and is intended for drinking.