diclofenac
noun
di·clo·fe·nac
| \ dī-ˈklō-fə-ˌnak
\
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Medical Definition of diclofenac
: a nonsteroidal anti-inflammatory drug used in the form of its sodium salt C14H10Cl2NNaO2 or potassium salt C14H10Cl2KNaO2 especially to treat the symptoms of rheumatoid arthritis, osteoarthritis, and ankylosing spondylitis — see voltaren