#stepparent  the spouse of your parent by a subsequent marriage
  supertype:  parent  a father or mother; one who begets or one who gives birth to or nurtures and raises a child; a relative who plays the role of guardian
  subtype:  stepfather  the husband of your mother by a subsequent marriage
  subtype:  stepmother  the wife of your husband by a subsequent marriage

No statement uses or specializes stepparent; click here to add one.