tripartition†, trichotomy; third, third part.
V. trisect, divide into three parts.
Adj. trifid; trisected &c v.; tripartite, trichotomous†, trisulcate†.
Triadelphous†, triangular, tricuspid, tricapsular†, tridental†,
tridentate, tridentiferous†, trifoliate, trifurcate, trigonal†,
trigrammic†, trigrammatic†, tripetalous†, tripodal, tripodic†,
triquetral†, triquetrous†.