- abnormal of white blood cell
- abnormal operation
- abnormal operation of steam turbogenerator
- abnormal pressure
- abnormal psychology
- abnormal rare-earth element chemistry
- abnormal redshift
- abnormal refraction
- abnormal rolling of re-entry vehicle
- abnormal series
- abnormal sexual behavior
- abnormal singularity
- abnormal sound
- abnormal spectrum
- abnormal subgroup
- abnormal temperature of the steam
- abnormal toxicity test for drugs
- abnormal uterine bleeding
- aboaclusion
- aboardage
- a board used to seal documents in preservation and transmission
- A Boat Carved from Walnuts
- ABO blood group
- ABO blood group system
- ABO blood type antigen