n.
Pronunciation: ' del-t ə
Function: noun
Etymology: Middle English deltha, from Greek delta, of Semitic origin; akin to Hebrew d ā leth daleth
Date: 13th century
1 : the 4th letter of the Greek alphabet ― see ALPHABET table
2 : something shaped like a capital Greek delta especially : the alluvial deposit at the mouth of a river
3 : an increment of a variable ― symbol Δ
4 : DELTA WAVE
– del · ta · ic \ del- ' t ā -ik \ adjective