A form of syllogism in scholastic logic. The name is from a medieval mnemonic poem, where its vowels reflect the syllogism's standard form of IAI-4.
The Oxford English Dictionary
notes that Dimaris was formerly called Drimatis or Dimatis.
Barbara, Celarent, Darii, Ferio que prioris;
Cesare, Camestres, Festino, Baroko secundae;
Tertia, Darapti, Disamis, Datisi, Felapton,
Bokardo, Ferison, habet; Quarta in super addit
Bramantip, Camenes, Dimaris, Fesapo, Fresison