YY

YY or variants may refer to:

YY.com, a major Chinese social network
yy (digraph), digraph used in various Latin alphabets
Yy (musician), Canadian musician
YY, the call sign prefix for radio stations in Venezuela
Y. Y., pseudonym of Robert Wilson Lynd (1879–1949), Irish essayist
Peptide YY 3-36, a peptide secreted by the gut in response to a meal, and reduces appetite
YY, the production code for the 1969 Doctor Who serial The Space Pirates

See also