There are 2 main definitions of Hb in English:

Hb1

Line breaks: Hb

symbol

Haemoglobin: your Hb level will be tested early in pregnancy

Definition of Hb in:

There are 2 main definitions of Hb in English:

HB2

Line breaks: HB

abbreviation

1.1 (also hb) Hardback: £12.99 hb/£8.99 pb
1.2Hard black (used in describing a medium grade of pencil lead).
1.3The political wing of the Basque separatist organization ETA.
[abbreviation of Basque Herri Batasuna 'United People']

Definition of Hb in: