Definition of "HB"

Initialism of Hansestadt Bremen. The German city of Bremen. (Used on licence plates and informally in other contexts.)  examples

hard black (describing a pencil that makes lighter marks than a grade B, but darker marks than a grade H pencil).  quotations  examples

(stars) Initialism of horizontal branch.  examples

(slang, seduction community) A hot babe, someone pickup artists try to seduce. (Usually followed by a number in the 1-10 scale of physical beauty, e.g. HB10.)

(health) Initialism of homebirth.  examples

(law, politics, often followed by a number) Initialism of house bill (“a bill proposed in or passed by a legislative house”). (Compare SB.)  examples

(American football) Initialism of halfback.  examples

(Internet slang, text messaging) Abbreviation of happy birthday.

(transitive, Internet slang) To hard-block.  quotations