[treesknees]

>quater

Quater is not a unit (or a word) so why would it ever mean 'fourth'? Quarter is probably the word you're looking for.

[pitspotter2]

I did find an obscure prefix:

https://www.merriam-webster.com/dictionary/quater-

[dylan604]

One is a typo, the other is using the wrong word.

[djur]

"Forth" is just as easy a typo for "fourth" as "quater" is for "quarter". It's uncharitable to assume someone is using the wrong word when it's just as likely that they made a typo or misspelled the correct word.

[dylan604]

Except that's not what happened if you read the other comments