The application is to be submitted in sextuplicate
adjective
2.
having or consisting of six identical parts; sixfold
3.
sixth
transitive verb
4.
to make six copies of
5.
to make six times as great
Word origin
[1650–60; sextu(ple) + -plicate, as in duplicate]This word is first recorded in the period 1650–60. Other words that entered Englishat around the same time include: backhand, gas, parade, pony, siphon