Lexical Definition

‎ὀψάριον‎ opsárion (op-sar'-ee-on) fish ^G:N-N
neuter of a presumed derivative of the base of ‎ὀπτός‎

fish.

• a relish to other food (as if cooked sauce), i.e. (specially), fish (presumably salted and dried as a condiment)

Abbott-Smith

** ὀψάριον, -ου, τό (dimin. of ὄψον, (1) cooked meat; (2) a relish or dainty, esp. fish, cf. MGr. τὸ ψάρι, fish; in comic poets and late prose writers only), [in LXX: To 2:2 א (B ὄψον)*;]
fish: Jo 6:9, 11 21:9, 10, 13.†

Abbott-Smith References

Liddell-Scott-Jones

ὀψάριον-άριον, τό,

diminutive of ὄψον, [Refs 5th c.BC+]; λαγύνιον ταριχηροῦ (i.e. -ῶν) ὀψάριοναρίων a jar of pickled fish, [NT+1st c.AD+]

_{LSJ Scripture Refs: John.6.9}