RhymeZone: staurogram definitions

Definitions of staurogram:

noun: A ligature, ⳨, of the Greek letters τ and ρ or Coptic letters ⲧ and ⲣ, later used as a symbol of the cross in early Christianity and remaining in use as a ligature in abbreviations of the words σταυρός and σταυρόω.

(Definitions from Wiktionary)