cautious

Adjective

• avoiding excess
  • a conservative estimate
    

• showing careful forethought; never making swift decisions"
  • reserved and cautious
    
  • a cautious driver
    

Noun

• people who are fearful and cautious
  • whitewater rafting is not for the timid
    

Related words

• Synonyms: 
  conservative , timid
• Antonyms: 
  incautious , brave