black iron
Free weights as opposed to exercise machinesFree weights as opposed to exercise machines.
Meaning
1 senses(uncountable)Free weights as opposed to exercise machines.
Origin
From the typical paint color and material traditionally used for free weights (cast iron wFrom the typical paint color and material traditionally used for free weights (cast iron with black paint).
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Lessons for this word
1 lessons- A1Countable and uncountable nouns — Because it can be uncountable