Related Clues:

• Proper thing?
• Common thing in a sentence?
• Safety standards
• DPEF off by one, for example!
• Proper --
• Basic part of speech
• Bill or gates, e.g
• Rock, paper, or scissors
• Subject of a verb
• What programmers write
• "Bar" or "airport" follower
• Building contractor's concern
• It may be abstract or concrete
• Word that is an example of itself
• System of ethics - cipher