Synonyms for Senior (same or very similar meaning)
WordNet sense 1 (having a higher rank):
superior
WordNet sense 2 (of the elder of two boys with the same family name):
major
WordNet sense 3 (used of the older of two persons of the same name especially used to distinguish a father from his son):
elder, older, sr.
WordNet sense 4 (advanced in years; (`aged' is pronounced as two syllables)):
elderly, aged, aged
WordNet sense 5 ((used especially of persons) having lived for a relatively long time or attained a specific age):
old
WordNet sense 6 (used of the fourth and final year in United States high school or college):
fourth-year
WordNet sense 7 (coming after all others in time or space or degree or being the only one remaining):
last
From the ODE community, based on WordNet
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