daka : [nt.] water.

A.P. Buddhadatta Mahathera, Concise Pali-English and English-Pali Dictionary [available as digital version from Metta Net, Sri Lanka]

Daka (nt.) [=udaka, aphaeretic from combns like sīto- daka which was taken for sīto+daka instead of sīt' odaka] Vin iii.112; S iii.85; A ii.33=Nd2 420 B3 (: the latter has udaka, but Nd1 14 daka).
   -- āsaya (adj.) (beings) living in water A ii.33≈; -- ja (adj.) sprung from water, aquatic J i.18 (thalajā d pupphā); -- rakkhasa a water -- sprite J i.127, 170; vi.469.

Pali-English Dictionary, TW Rhys Davids, William Stede,

daka n. = ud○, water Phetk. xvii
• cf. dagârgala

Sanskrit-English Dictionary, by M. Monier William