In the name Firth of Forth what is the etymology of the word Forth?

In the name Firth of Forth what is the etymology of the word Forth? I remember it having a meaning but couldn’t find any reference to it online.

Did you mean to ask for the etymology of Firth? Forth is the name of a river and firth is an estuary leading to that river. Firth is related to fjord, narrow inlet.

It’s all right here: Firth of Forth - Wikipedia

On an unrelated note, I was just there a few days ago. The river spanning the Firth of Forth goes to Fife.

I meant Forth. I thought I remembered a background story to the name of the river.

Got it. From that page:

Forth stems from the name of the river; this is *Vo-rit-ia (slow running) in Proto-Celtic, yielding Foirthe in Old Gaelic and Gweryd in Welsh.

Looks like it means “slow running”

Thanks RitterSport.

Looks like the etymology traces to per (forward ) in Proto Indo European root. Lots of Hindi words are also derived from the same prefix meaning approximately the same.

That appears to be the wrong etymology for this usage. The Forth here has nothing to do with forward, etc.

And is that divided into fifths? If not, it ought to be.

In 2017 they opened the third Forth bridge to Fife.

The Firth of Fifth is something completely different.

Youtube link to song “Firth of Fifth” by Genesis, for those who don’t want to click

Wherever there are four Scotsmen, there will be a fifth.

Pity the radio/TV announcer who comes across this while reading the Scottish football results:

East Fife 4 - Forfar 5

Plus the announcer had to watch Scottish football. <zing!>

In 1963/64 Forfar beat East Fife 5-4 at home.