Synonyms for Expression (same or very similar meaning)
WordNet sense 1 (a word or phrase that particular people use in particular situations):
locution, saying
WordNet sense 2 (the communication (in speech or writing) of your beliefs or opinions):
verbal expression, verbalism
WordNet sense 3 (the style of expressing yourself):
formulation
WordNet sense 4 (expression without words):
manifestation, reflection, reflexion
WordNet sense 5 (a group of symbols that make a mathematical statement):
formula
WordNet sense 6 (a group of words that form a constituent of a sentence and are considered as a single unit):
construction, grammatical construction
WordNet sense 7 (the feelings expressed on a person's face):
face, look, aspect, facial expression
From the ODE community, based on WordNet
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