Meaning

• To visit (a person); to pay a call to.

  "I really should call on my aunt more often."

• To select (a student in a classroom, etc.) to provide an answer.

  "He sat there, baffled, hoping nobody would call on him."

• (also call upon) To request or ask something of (a person); to select for a task.

  "The king called on his subjects to take up arms and defend the kingdom."

• (also call upon) To have recourse to.

  "Exhausted, he called on his last ounce of strength."

• To correct; to point out an error or untruth.

  "The salesman persisted in quoting a rate higher than was listed, until we called him on it."