σφεῖς

Etymology
The consonantism began in the dative, originally the dative of the reflexive pronoun, from. Later the σφ-cluster spread to the rest of the paradigm, and the pronoun acquired a nonreflexive plural sense. The ending -εῖς was added by analogy with other pronominal forms, such as. The σφ-cluster also spread to the third-person dual pronoun and  the second-person dual pronoun.

Pronoun

 * 1)  they
 * 2)  themselves

Usage notes
Oblique cases (not nominative) used frequently by Homer. In Attic, the plurals of and  are more commonly used as personal pronoun and reflexive. For the singular forms, see.