Xi
WordNet
adjective
(1) Being one more than ten
noun
(2) The 14th letter of the Greek alphabet
(3) The cardinal number that is the sum of ten and one
WiktionaryText
Noun
- The name for the 14th letter of Classical and Modern Greek. The 15th in Ancient and Old Greek.
- Either of a pair of hyperons having spin 1/2, which decay into a lambda particle and a pion.