Synonyms for Really (same or very similar meaning)
WordNet sense 1 (in actual fact):
actually
WordNet sense 2 (in fact (used as intensifiers or sentence modifiers)):
truly, in truth
WordNet sense 3 (in accordance with truth or fact or reality):
genuinely
WordNet sense 4 (used as intensifiers; `real' is sometimes used informally for `really'; `rattling' is informal):
rattling, real, very, real, real
From the ODE community, based on WordNet
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