Synonyms for Interpreter (same or very similar meaning)
WordNet sense 1 (an advocate who represents someone else's policy or purpose):
representative, spokesperson, voice
WordNet sense 2 (someone who mediates between speakers of different languages):
translator
WordNet sense 3 ((computer science) a program that translates and executes source language statements one line at a time):
interpretive program
From the ODE community, based on WordNet
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