The Roman Map of Britain Voritamnio Kinneil, Bo'ness & Carriden
Volitanio (R&C 192) next
Its position suggests the emendation of Volita- to Vorita-. Kinneil (NS9780) is the next fort after Velunia Carriden (R&C 191) and on the River Forth.
Watson p.53 held that Forth is W. gwerid from O.British *Voritia 'the Slow-running One'.
This form is recorded as Ripae vadorum Forthin 970, Werid 12th.
This does not appear to be the same name as Ptolemy's Boderia or the Bodotria of Tacitus. The River Wear of Durham had two co-existing name forms, see Ekwall.
On the emendation to -amnio < -ănio: Lewis & Short amnis - m., (but sometimes f.) orig., any broad and deep-flowing, rapid water; a stream, torrent, river (hence, esp. in the poets, sometimes for a rapidly-flowing stream or a torrent rushing down from a mountain = torrens; sometimes for a large river, opp. fluvius (a common river); sometimes also for the ocean as flowing round the land; it most nearly corresponds with our stream.