There are several synonyms for the word "stepgrandfather." One term that is commonly used is "step-grandpa," which is a more informal way of referring to a stepgrandfather. Another term is "step-grandfather," which is the official title for a man who becomes a grandfather through marriage. other synonyms include "bonus grandpa," "grandfather-in-law," "surrogate grandfather," and "adopted grandfather." All of these terms refer to a man who is not biologically related to his grandchildren but has become a beloved and respected figure in their lives through marriage, adoption, or other familial bonds. Regardless of the term used, the role of a stepgrandfather is important and should be celebrated and appreciated.