Supplanted is a word that refers to the act of replacing or overtaking someone or something. There are a number of different synonyms that can be used to capture this meaning, each with their own subtle differences. For example, "usurped" is a synonym that implies a more forceful takeover or seizure than "supplanted" does. "Displaced" is a term that suggests someone or something has been moved out of its original position or location. "Overthrown" is another synonym for "supplanted" which suggests a violent or dramatic change, often in a political context. Ultimately, the choice of synonym will depend on the context in which "supplanted" is being used.