ἀββᾶ
From LSJ
English (Thayer)
(WH (βά), Hebrew אָב father, in the Chaldean emphatic state, אַבָּא i. e. ὁ πατήρ, a customary title of God in prayer. Whenever it occurs in the N. T. (אַבָּא, through frequent use in prayer, gradually acquired the nature of a most sacred proper name, to which the Greek-speaking Jews added the appellative from their own tongue.
Greek Monotonic
Ἀββᾶ: Εβρ. λέξη, πατέρας, σε Καινή Διαθήκη
Middle Liddell
English (Strong)
of Chaldee origin (אַב); father as a vocative: Abba.
Greek (Liddell-Scott)
ἀββᾶ: Ἑβρ. λέξις = πατήρ, Εὐαγ. Μάρκ. ιδ΄. 36.
Russian (Dvoretsky)
ἀββᾶ: ὁ (евр.) отец T.