H
H appears in everyday contexts as the abbreviation for hour, while in scientific and technical settings it can stand for hydrogen, a header file in programming, or denote high or horrific levels.
Medical
Head
Hematachometer
Heterosexual
Histidine
Hands
Hepatitis
Haploid
Hospitalization
Hearing
Health
mustard gas
health and safety
hysterectomy and sterilisation
Miscellaneous
Hour
Half
Hell
Height
Henry
Harry
Howard
Hannah
Harriet
Helen
Hope
Heads
Hamilton
Harold
Hector
Horatio
Horace
Hog
Horse
Ham
Hue
And How
Harrison
Community
Governmental
Helpful
Hero
Honesty
Honor
Hospital
Height (Altitude)
Undistilled Sulfur Mustard gas (military designation)
Homicide
International
Academic & Science
Hydrogen
High
Humanities
Hall
Harvard
Hamming
Handle
Hot
Hilly
form H (break; break) contacts
Honors
Planck constant