Usage: 3 forms in 3 verses
Form Translated As     In Verse(s)
κατερρύηκεν have flown down LXX.Jer.8.13
καταρρείν will flow down LXX.1Sam.2.33
κατέρρει flowed down LXX.1Sam.21.13

Liddell-Scott-Jones

καταρρέω (katarreō) to flow down G:V

καταρρέω,

perfect -ερρύηκα: aorist -ερρύην (see. below):— flow down, [Refs 8th c.BC+]; ποταμοὶ κατ᾽ ὄρεσφι . [Refs 5th c.BC+]; of rivers, παρὰ τὴν Ἄλτιν κ. [Refs 5th c.BC+].

__2 of men, stream, rush down, [Refs 6th c.BC+]; οἱ δὲ ἐμπαλασσόμενοι κατέρρεον, i. e. into the river, [Refs 6th c.BC+]; sink down, [Refs 5th c.BC+]; διὰ τοῦ τέγους κ. [Refs 6th c.BC+].
__3 of fruit, leaves, etc., fall, drop off, [Refs 5th c.BC+]
__4 fall in ruins, [Refs 4th c.BC+]: metaphorically, [Refs 4th c.BC+]; σιγᾷ κατερρύη μέλος uncertain in [Refs 5th c.BC+]; of a crater, fall in, [Refs 2nd c.BC+]; of a roof, [Refs 2nd c.AD+] having collapsed, [Refs]
__5 κ. ἔς τινα come to, fall to the lot of, [Refs 3rd c.BC+]
__6 burrow, [Refs 4th c.BC+].
__7 metaphorically, fall into, [Refs 3rd c.BC+]
__II run down, drip with, [Refs 5th c.BC+]:—and in passive, αἵματι, ἱδρῶτι καταρρεῖσθαι, [Refs 1st c.AD+]