heptakaidecahedronEtymologyFrom Ancient Greek ἑπτᾰ́ (heptắ, “seven”) + καί (kaí, “and”) + δέκᾰ (dékă, “ten”) + -hedron.heptakaidecahedron means Synonym of heptadecahedron. Lexicurio rates it Rare gem — a strength score of 82 out of 100.nounSynonym of heptadecahedron.“The lacunar pattern of this grain therefore includes six tetragonal and nine hexagonal faces. Relating this to polyhedrons, we find that no pentakaidecahedron with such a combination of faces can exist (see page 199). If, however, the two polar areas be regarded as filled-in hexagonal lacunae, making 17 lacunae in all, the pattern corresponds to a heptakaidecahedron with 6 tetragonal and 11 hexago”