What is the meaning of Bah?

Expressing contempt, disgust, or bad temper.

Alternative spelling of baa (the cry of a sheep or goat).

Used for emphasis; softens a suggestion.

An exclamation of disapproval, contempt or disgust: bah, yuck

No.

An exclamation to fill space, often used as an intensifier; well, err, um

an exclamation of disgust: yuck, etc.

flood (overflow of water)

water

river

bet

flood.

an exclamation of scorn, disgust, contempt

an exclamation of intimacy

indicates astonishment, resignation and despise; usually used after noticing or hearing something you don't like or you don't know what to think about, to avoid commenting or giving an answer to a question

bah in Luciano Canepari, Dizionario di Pronuncia Italiana (DiPI)

flood (overflow of water)

Alternative form of abah

Alternative form of bapa

Abbreviation of bahasa.

Alternative form of bawah

Alternative form of

indicates disdain or unbelief

Source: wiktionary.org