referrer

/rɪˈfɜrər/
noun
  1. A person who sends someone to another person or place for help, information, or service.
    • The referrer receives a thank-you gift for each new client they send our way.
    • The doctor acted as a referrer when she sent her patient to a cardiologist.
    • As a referrer, you can track how many of your friends have signed up.
  2. A website or source that directs traffic to another website.
    • The analytics show that Google is the top referrer to our blog.
    • We track each referrer to see which sites send the most visitors.
    • A suspicious referrer may indicate spam traffic.