The paper aims at presenting a theoretical status of synonymy and isomorphism in linguistic literature as well as the way English language users 'practie' synonymity in verbal interactions. A critical survey of the British philosophical tradition towards synonymy and the examples of the real uses of practical synonyms J. Svartvik, R. Quirk, A Corpus of English Conversation, Lund 1980 lead to the conclusion that synonymity is not a homogenous phenomenon but should be treated as a lingustic manifestation of intederminacy and gradability of some linguistic facts.Zadanie pt. „Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki” nr 885/P-DUN/2014 ...