Lexical Definition

‎εὐφραίνω‎ euphraínō (yoo-frah'-ee-no) to celebrate ^G:V
from ‎εὖ‎ and ‎φρήν‎

fare, make glad, be (make) merry, rejoice.

• to put (middle voice or passively, be) in a good frame of mind, i.e. rejoice

Abbott-Smith

εὐφραίνω [in LXX chiefly for שָׂמַח, qal, pi. ;]
to cheer, gladden: c. acc pers., opp. to λυπεῖν, II Co 2:2. Pass., to be happy, rejoice, make merry: Lk 15:32, Ac 2:26 (LXX) Ro 15:10 (LXX), Ga 4:27 (LXX), Re 11:10 12:12; seq. ἐν, Ac 7:41; ἐπί c. dat., Re 18:20; of merry-making at a feast (III Ki 4:20; cf. Kennedy, Sources, 155; Field, Notes, 69 f.), Lk 12:19 15:23, 24, 29 (LXX) (λαμπρῶς) Lk 16:19.†

Abbott-Smith References

Liddell-Scott-Jones

εὐφραίνω,

Epic dialect ἐϋφρ-, future Attic dialect εὐφρᾰνῶ [Refs 4th c.BC+], Ionic dialect and Epic dialect εὐφρανέω [Refs 8th c.BC+]aorist 1 εὔφρᾱνα or ηὔφρ-[Refs 5th c.BC+]; Epic dialect εὔφρηνα [Refs 8th c.BC+], subjunctive ἐϋφρήνῃς [Refs]:—passive, with future middle εὐφρᾰνοῦμαι [Refs 5th c.BC+]; Ionic dialect 2nd pers. singular εὐφρανέαι (variant -έεαι) [Refs 5th c.BC+]; also passive εὐφρανθήσομαι [Refs 5th c.BC+]aorist 1 εὐφράνθην or ηὐ- [Refs 5th c.BC+]: (εὔφρων):—cheer, gladden, εὐφρανέειν ἄλοχον [Refs 8th c.BC+]; νόον, φρένα, [Refs 8th c.BC+]

__II passive, make merry, enjoy oneself, εὐφραίνεσθαι ἕκηλον [NT+8th c.BC+]; τινι at or in a thing, [Refs 5th c.BC+]participle, εὐφράνθη ἰδών was rejoiced at seeing, [Refs 5th c.BC+]; τὰ ἐμὰ εὐ. enjoy a pleasure in my stead, [Refs 2nd c.AD+]

_{LSJ Scripture Refs: Luke.16.19}