μονόπαις
From LSJ
ἐν τῷ διὰ τῆς κατασκευῆς παρεπιφαινομένῳ περίττῳ → through some excess thing which results through poetic elaboration
English (LSJ)
παιδος, ὁ, ἡ,
A only child, E.Alc. 906 (lyr.), Sammelb.5873. II having one child, IG12(9).293 (Eretria, iv/iii B.C.).
German (Pape)
[Seite 204] παιδος, ὁ, der einzige Sohn, Eur. Alc. 909.