n.
Pronunciation: ' lam-d ə
Function: noun
Etymology: Middle English, from Greek, of Semitic origin; akin to Hebrew l ā medh lamed
Date: 15th century
1 : the 11th letter of the Greek alphabet ― see ALPHABET table
2 : an uncharged unstable elementary particle that has a mass 2183 times that of an electron and that decays typically into a nucleon and a pion