chalkdust
The fine white powder remaining after chalk is erased from a chalkboardThe fine white powder remaining after chalk is erased from a chalkboard.
Meaning
1 senses(uncountable)The fine white powder remaining after chalk is erased from a chalkboard.
Origin
From chalk + dust.From chalk + dust.
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Lessons for this word
1 lessons- A1Countable and uncountable nouns — Because it can be uncountable