potash alum

8.3

A white crystal used to dye cloth, purify water, and treat skin

noun
/ˈpɒtæʃ ˈæləm/

Specialized

: alumbre de potasa

In traditional textile dyeing, potash alum is often used as a mordant.

Examples

The solution contained potash alum for water purification.
The chemist demonstrated the properties of potash alum by dissolving it in water.
Adding potash alum to the water helped clarify the solution during purification.
Many textile industries use potash alum in dyeing processes.
Adding potash alum to the water helped clarify the solution during purification.
In traditional textile dyeing, potash alum is often used as a mordant.
Many textile industries use potash alum in dyeing processes.

Synonyms

alum

vspotash alum

Specialized

1 8.2

A white salt used to stop bleeding, fix dyes, and clean water

is a specific member of that group used for dyeing and purification

potassium alum

vspotash alum

Specialized

6.5

A white crystal people use to clean water, help dye cloth, and make skin less oily

is the same substance but referred to by the alternative traditional name

Surface Forms

potash alum singular

potash alums plural

Morphology

potash + alum

The compound denotes an alum that contains potash (potassium), so a learner who knows 'potash' (a potassium compound) and 'alum' (a double-sulfate chemical) can infer it is the potassium-containing alum. Although it is specialized chemical vocabulary, its meaning is compositionally predictable and follows standard naming logic found across languages.

Etymology

Potash alum comes from old craft words: potash was a potassium salt made by soaking wood ashes in water, and alum was the common salt used for dyeing. That's why potash alum is the white salt used to 'fix dyes' to cloth and to 'purify' water.