Wordnet 3.0
NOUN (1)
1. 
 a common language used by speakers of different languages; 
- Example: "Koine is a dialect of ancient Greek that was the lingua franca of the empire of Alexander the Great and was widely spoken throughout the eastern Mediterranean area in Roman times"[syn: lingua franca, interlanguage, koine]
WordNet (r) 3.0 (2006):
interlanguage
    n 1: a common language used by speakers of different languages;
         "Koine is a dialect of ancient Greek that was the lingua
         franca of the empire of Alexander the Great and was widely
         spoken throughout the eastern Mediterranean area in Roman
         times" [syn: lingua franca, interlanguage, koine]