filum aquæ

The thread or middle of any river or stream which divides countries, manors, &c.

♦ File du mer, the high tide of the sea.

filum
fīlum, i. n. (also filus, i, m., acc. to Arn. 1, 36 dub., plur. heterocl., fili, Luc. 6, 460) [for f...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.
filum
fīlum ī, n a thread, string: Caeca regens filo vestigia, V.: deducens pollice filum, O.: Candelae, ...

An Elementary Latin Dictionary
retractus aquæ
An old law-term for the ebb or return of tide. ...

The Sailor's Word-Book