HAD
HADAL
HADARIM
HADAWAY
HADDEN
HADDEST
HADDIE
HADDIES
HADDING
HADDOCK
HADDOCKS
HADE
HADED
HADEDAH
HADEDAHS
HADES
HADING
HADITH
HADITHS
HADJ
HADJEE
HADJEES
HADJES
HADJI
HADJIS
HADROME
HADROMES
HADRON
HADRONIC
HADRONS
HADROSAUR
HADROSAURS
HADROSAURUS
HADROSAURUSES
HADS
HADST

36 words start with HAD.