Definitions of legitimate:

• verb:   make (an illegitimate child) legitimate; declare the legitimacy of (someone)
• verb:   show or affirm to be just and legitimate
• verb:   make legal
• adjective:   of marriages and offspring; recognized as lawful
• adjective:   in accordance with recognized or accepted standards or principles

  Example: "Legitimate advertising practices"

• adjective:   in accordance with reason or logic
• adjective:   authorized, sanctioned by, or in accordance with law

  Example: "A legitimate government"