The term "most annexed" can be defined as the state of being added to something larger. It can be substituted with other words that convey the same meaning. Some synonyms for "most annexed" could include "incorporated," "attached," "joined," "united," "merged," or "absorbed." These words can be used interchangeably depending on the context of the sentence. For example, instead of saying "the most annexed territory," one could say "the territory that was incorporated into the larger country." Finding the right synonym can help diversify one's vocabulary and improve communication skills.