Cf. tuballaṣ-qinassa (bird-name) (CDA 408).
Derived words: balāṭu 'life' (CAD B 46, AHw. 98), balṭu 'alive, safe and sound, surviving, taken alive' (CAD B 66, AHw. 100), balṭānu 'alive' (CAD B 66, AHw. 100), balṭūtu 'state of being alive' (CAD B 69, AHw. 100); bulṭu 'life, lifetime' (CAD B 311, AHw. 137); muballiṭānu 'person who has kept someone alive' (CAD M₂ 157, AHw. 665); muballittu 'barrage, weir (in a canal), cage' (CAD M₂ 157, AHw. 665); nablaṭu 'healing, life-giving' (CAD N₁ 25, AHw. 698); tablittu 'fodder, victuals' (CAD T 29, AHw. 1299).
Is usually compared to Ugr. plṭ, Hbr. plṭ, Syr. plṭ ‘to escape’ (Fronzaroli 1965b, 250, 263, 267; instead of Arb. flt ‘to escape’, phonetically remote, cf. rather Arb. bālaṭa ‘to flee’, buluṭ- ‘fugitives’, LA 7 300).
Hapax. A WS feminine form of *baˁl - “lord”.
As a synonym of bēlu “lord”, the present form must go back to WS *baˁl -. Following SAD 1 7, one has to assume that a nisbah suffix was attached to *baˁl -, even if this is rather unusual.
It is conceivable that Akk. ballukku and Sum. (šem)bulug were borrowed independently from a third language.
Or palsû.
Probably of Sumerian origin (perhaps a “learned” loanword), but the etymon is obscure.
The original form is baštu rather than baltu (George 2016, 113f.). No etymology can be suggested.