(Internet slang) Abbreviation of hat tip.

Initialism of hot and cold (water).

(fandom slang) Initialism of hurt/comfort.

(Internet slang, text messaging) Abbreviation of hold on.

Alternative form of aitchbone

Alternative letter-case form of h/c.

Initialism of postage, processing and handling.

(motorsports) Initialism of motor generator unit, heat. (an energy recovery system; a motor generator unit which harvests thermal energy from the exhaust via the turbocharger)

Abbreviation of Hakadosh Baruch Hu.

Acronym of high school.