[1400–50; late ME ‹ ML excūsātōrius, equiv. to LL excūsā(re) to excuse + -tōrius-tory1]This word is first recorded in the period 1400–50. Other words that entered Englishat around the same time include: dial, peg, separate, structure, transit-tory is a suffix occurring in loanwords from Latin, orig. adjectival derivatives of agentnouns ending in -tor (predatory); also forming adjectival derivatives directly from verbs (obligatory; transitory)