Acronym  ... 
Name 
dual of uniform triangular prism, triangular dipyramid (but not tridpy), o3m3o3o cell 
©  
Inradius  1/sqrt(21) = 0.218218 
Vertex figure  [T^{3}], [t^{4}] 
Dihedral angles 

Dual  trip 
Confer 

External links 
The triangles {(t,t,T)} have vertex angles t = arccos[(1+5 sqrt(5))/16] = 40.423604° resp. T = arccos(1/8) = 97.180756°.
Note that the term dipyramid, even so stated above, in general says nothing about the relative ratio of the to be chosen lacing edge size. There is an equilateral dipyramid as well, tridpy (n=3). – Whereas in here the edge ratio is chosen such as to match its duality to the trip!
The a edge, provided in the below description, only qualifies as pseudo edge wrt. the full polyhedron. In fact it rather describes its tiptotip distance.
Incidence matrix according to Dynkin symbol
m m3o = oxo3ooo&#yt → both heights = a/2 = 1/3 y = 2/3 (pt  pseudo {3}  pt) o..3o..  1 * *  3 0 0  3 0 [T^{3}] .o.3.o.  * 3 *  1 2 1  2 2 [t^{4}] ..o3..o  * * 1  0 0 3  0 3 [T^{3}] +++ oo.3oo.&#y  1 1 0  3 * *  2 0 y .x. ...  0 2 0  * 3 *  1 1 x .oo3.oo&#y  0 1 1  * * 3  0 2 y +++ ox. ...&#y  1 2 0  2 1 0  3 * {(t,t,T)} .xo ...&#y  0 2 1  0 1 2  * 3 {(t,t,T)}
m m3o = ao ox3oo&#zy → height = 0 a = y = 2/3 (tegum product of aline with {3}) o. o.3o.  2 *  3 0  3 [T^{3}] .o .o3.o  * 3  2 2  4 [t^{4}] +++ oo oo3oo&#y  1 1  6 *  2 y .. .x ..  0 2  * 3  2 x +++ .. ox ..&#y  1 2  2 1  6 {(t,t,T)}
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