Dictionary Definition

flin•go |ˌflɪŋgəʊ|

noun ( pl. -gos or -goes) informal often humorous or derogatory

1. a localised English dialect heavily influenced by facebook : his lack of fluency in flingo marked his advanced age. See note at DIALECT.
2. the vocabulary, jargon, and mangled grammar endemic to a particular online community : “you’re”, known in flingo as “your”, is a contraction of “you are”, not to be confused with the possesive adjective; status updates in which a slide from third person to first or second person are prime examples of flingo.

ORIGIN early 21st cent.: probably via English lingo via Portuguese lingoa from Latin lingua ‘tongue.’ See also myspeech and leetspeak.

SOURCE first use attributed to Kristy Freney.