overzealous (adj.)
- accident-prone
- balking
- balky
- bigoted
- breakneck
- bullheaded
- careless
- case-hardened
- delirious
- desperate
- devil-may-care
- dogged
- dogmatic
- extravagant
- extreme
- extremist
- fanatic
- fanatical
- febrile
- feverish
- frantic
- frenetic
- frenzied
- furious
- haggard
- hardheaded
- harum-scarum
- hasty
- headlong
- headstrong
- hectic
- hotheaded
- hurried
- hysteric
- impetuous
- infatuated
- inordinate
- insane
- intolerant
- irrational
- mad
- mulish
- obstinate
- opinionated
- overanxious
- overeager
- overenthusiastic
- perfervid
- persevering
- pertinacious
- pigheaded
- precipitant
- precipitate
- precipitous
- rabid
- reckless
- restive
- sanctimonious
- self-willed
- set
- slapdash
- stiff-necked
- strong-willed
- stubborn
- sulky
- sullen
- tenacious
- uncooperative
- unreasonable
- unregenerate
- wanton
- wild
- wild-eyed
- willful
- zealous
