I.What is Coherence? Co-is a Latin prefix meaning“together''or“with” According to Cambridge Advanced Learner's Dictionary,coherence means when the parts of something fit together in a natural or sensible way1. What is Coherence? Co- is a Latin prefix meaning “together” or “with”. According to Cambridge Advanced Learner’s Dictionary, coherence means “when the parts of something fit together in a natural or sensible way ”