Lexical Definition

‎οἰκουμένη‎ oikouménē (oy-kou-men'-ay) world ^G:N-F
feminine participle present passive of ‎οἰκέω‎ (as noun, by implication, of ‎γῆ‎)

earth, world.

• land, i.e. the (terrene part of the) globe
• specially, the Roman empire

Abbott-Smith

οἰκουμένη, -ης, ἡ (fem. pres. pass. ptcp. of οἰκέω; sc. γῆ), [in LXX chiefly for תֵּבֵל, אֶרֶץ;]
the inhabited earth;
(a) in cl., the countries occupied by Greeks, as disting. from barbarian lands (Hdt., Dem., al.);
(b) in later writers, the Roman world: Lk 2:1, Ac 11:28 24:5; by meton., of its inhabitants: Ac 17:6 19:27;
(c) in LXX (Ps 22 (23):1* 70 (71):8*, al.) and NT, also of the whole inhabited world: Mt 24:14, Lk 4:5 21:26, Ro 10:18, He 1:6, Re 3:10 16:14; by meton. (ut supr.), Ac 17:31, Re 12:9;
(d) of the Messianic age, ἡ οἰ. ἡ μέλλουσα = ὁ αἰὼ ὁ μέλλων: He 2:5.†

Abbott-Smith References

Liddell-Scott-Jones

οἰκουμένη-η

(i.e. γῆ), ἡ, inhabited region, see at {οἰκέω} [Refs 4th c.BC+]; then the Greek world, opposed to barbarian lands, [Refs 4th c.BC+] = the inhabited world (including non-Greek lands, as Ethiopia, India, Scythia), as opposed to possibly uninhabited regions,[Refs 4th c.BC+] = our world (= Asia, Libya, Europe); οἰκουμένηαι worlds,[LXX+4th c.BC+]; loosely, the whole world, [Refs 4th c.BC+]: so perhaps in some passages cited under [Refs]

__II the Roman world, ὁ ἀγαθὸς δαίμων (etc.) τῆς οἰ., i.e. the Emperor, [NT+1st c.AD+]
__III ἡ οἰ. ἡ μέλλουσα the world to come, i.e. the kingdom of Christ, [NT]

_{LSJ Scripture Refs: Luke.2.1 ☩ Acts.17.6 ☩ Heb.2.5}