pannus
noun
pan·nus
| \ ˈpan-əs
\
\
plural panni\ ˈpan-ˌī
\
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Medical Definition of pannus
1
: a vascular tissue causing a superficial opacity of the cornea and occurring especially in trachoma
2
: a sheet of inflammatory granulation tissue that spreads from the synovial membrane and invades the joint in rheumatoid arthritis ultimately leading to fibrous ankylosis