Main definitions of hb in US English:

: Hb1HB2

Hb1

  • Hemoglobin.

    ‘your Hb level will be tested early in pregnancy’

Main definitions of hb in US English:

: Hb1HB2

HB2

abbreviation

  • 1Half board.

    ‘twin rooms with facilities on an HB basis’
  • 2also "hb"Hardback.

    ‘$12.99 hb/$8.99 pb’
  • 3Hard black (used in describing a medium grade of pencil lead).

  • 4The political wing of the Basque separatist organization ETA.