Homeric and Early Attic ξύν (xún) and Mycenaean Greek 𐀓𐀱 (ku-su) are its supposed early form. If not, with difficulty ( -υ- < *-o- is expected, but -σ- < *-s- and -σ- < *-ξ- are not), from Proto-Indo-European *som-, from *sem-, it might be a composition of this and one other element. Alternatively, it may be a phonologic combination of *sem- with *ḱóm by combining the initial consonant sounds of these related stems.
- In compounds it has similar applications, including completeness.
- σύν in Liddell & Scott (1940) A Greek–English Lexicon, Oxford: Clarendon Press
- σύν in Bailly, Anatole (1935) Le Grand Bailly: Dictionnaire grec-français, Paris: Hachette
- σύν in Cunliffe, Richard J. (1924) A Lexicon of the Homeric Dialect: Expanded Edition, Norman: University of Oklahoma Press, published 1963
- G4862 in Strong’s Exhaustive Concordance to the Bible, 1979Woodhouse, S. C. (1910) English–Greek Dictionary: A Vocabulary of the Attic Language, London: Routledge & Kegan Paul Limited.
- Sihler, Andrew L. (1995) New Comparative Grammar of Greek and Latin, Oxford, New York: Oxford University Press, →ISBN