Liddell-Scott-Jones

καταδύω (kataduō) to descend into ^G:V

καταδύω

or κατα-δύνω:

__I intransitive, in active present καταδύνω and middle καταδύομαι: future -δύσομαι: aorist -εδῡσάμην, Epic dialect 2 and 3rd.pers. singular -δύσεο, -δύσετο:—active, aorist 2 κατέδυν: perfect καταδέδῡκα:—go down, sink, set, especially of the sun (as [Refs 8th c.BC+]; ἅμα.. ἠελίῳ καταδύντι[Refs 8th c.BC+]; καταδεδυκέναι τὴν [νῆσον] κατὰ θαλάσσης [Refs 5th c.BC+]; also of ships, to be sunk or disabled, [Refs 5th c.BC+]; κ. ὑφ᾽ ὕδατι duck under water, [Refs]; καταδεδυκώς having popped down, [Refs 5th c.BC+]
__I.2 go down, plunge into, with accusative, καταδῦναι ὅμιλον [Refs 8th c.BC+]; κατεδύσετο πουλὺν ὅμιλον[Refs 8th c.BC+]; καταδυσόμεθ᾽.. εἰς Ἀΐδαο δόμους we shall go down into.., [Refs 8th c.BC+]; εἰς φάραγγας, of hares, [Refs 5th c.BC+]; εἰς ἅπασαν [τὴν πόλιν] [Refs 5th c.BC+]; of souls, εἰς βυθὸν κ. [Refs 1st c.AD+]: with dative, sink into, ταῖς ὁμοιοπαθείαις [Refs 4th c.AD+]: frequently with a notion of secrecy, insinuate oneself, steal into, καταδύεται εἰς τὸ ἐντὸς τῆς ψυχῆς ὅ τε ῥυθμὸς καὶ ἁρμονία [Refs 5th c.BC+]; κ. ἡ ψῦξις ἕως πλείστου the cold penetrates most, [Refs 2nd c.AD+]
__I.3 slink away and lie hid, καταδύεσθαι ὑπὸ τῆς αἰσχύνης [Refs 5th c.BC+] (so absolutely, to be overcome with shame, ἐπὶ τῇ ἀγνοίᾳ [Refs 5th c.BC+]
__I.4 get into, put on, κατέδυ κλυτὰ τεύχεα [Refs 8th c.BC+]
__II causal, make to sink, rare in present, ἐμπίπτων καὶ καταδύων [Refs 5th c.BC+]: mostly in aorist 1, γαύλους καταδύσας [Refs 5th c.BC+]; in naval warfare, καταδῦσαι ναῦν cut it down to the water's edge, disable it, [Refs 5th c.BC+]; ἥλιον ἐν λέσχῃ κατεδύσαμεν we let the sun go down in talk, [Refs 3rd c.BC+]
__II.2 duck, τὴν κεφαλήν, in a bath, [Refs 1st c.AD+]