decaplet

From deca- (“ten”) +‎ -ple (“multiply”) +‎ -et (diminutive suffix); in ignorance of existence of decuplet.

decaplet (plural decaplets)

1. Alternative form of decuplet.
   • 1956, Peter Fleming, My Aunt's Rhinoceros, and Other Reflections‎^[1], page 78:

     "Medical opinion is that reported instances of multiple [human] births in excess of seven must be looked on with great suspicion," they write sternly; yet they do not deny us a somehow tantalizing glimpse of Ann Birch who, in 1781, is alleged to have produced decaplets of whom one girl survived to marry a Mr. Platt of Leeds.

   • 1989 July 30, “For the Record”, in Chicago Sun-Times‎^[2], page 4:

     There have been three cases reported of decaplets - multiple births of 10 children.