"Drouth" is an Irishism heard often in Ulysses. It is the same word as the English "drought," but instead of referring only to a prolonged period without rain––a condition of eastern Ireland at the time of the novel––it also applies to human thirst. This double usage preserves a linguistic tradition that apparently was once more widespread across the water.

John Hunt 2023

Drought in eastern Ireland in 2018. Source: www.reddit.com.

Brendan Behan: “I only drink on two occasions––when I am thirsty and when I’m not thirsty.” Source: www.telegraph.co.uk.