In geometry, the tridiminished rhombicosidodecahedron is one of the Johnson solids (J83).
It can be constructed as a rhombicosidodecahedron with three pentagonal cupolae removed.
Related Johnson solids are:
- J76: diminished rhombicosidodecahedron with one cupola removed,
- J80: parabidiminished rhombicosidodecahedron with two opposing cupolae removed, and
- J81: metabidiminished rhombicosidodecahedron with two non-opposing cupolae removed.
The 92 Johnson solids were named and described by Norman Johnson in 1966.