Definitions of alter:

• verb:   remove the ovaries of
• verb:   make an alteration to

  Example: "This dress needs to be altered"

• verb:   make or become different in some particular way, without permanently losing one's or its former characteristics or essence
• verb:   cause to change; make different; cause a transformation

  Example: "The advent of the automobile may have altered the growth pattern of the city"

• verb:   insert words into texts, often falsifying it thereby
• name:  A surname (rare: 1 in 100000 families; popularity rank in the U.S.: #9169)