What is the meaning of Foh?

An exclamation of abhorrence or contempt.

Pronunciation spelling of four

alternative form of fah

alternative form of fou

singular imperative of fōn

ugh!, phew!, yuck! (used to express disgust, particularly at a bad smell)

wow!, good grief!, bloody hell! (used to express exasperation, fatigue, or being overwhelmed)

Source: wiktionary.org