Question

what is meant by the statement that the wattage of the electric iron is 1000W?

Answer 1

The statement means the that the power of an electrical iron is 1000 Watt.

Power = Energy/Time

Means it consumes 1000 Joules of Energy per second.

Answer 2

statement that the wattage of the electric iron is 1000W means that
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the power of iron is 1000W 

1 W = 1J/s

which means the iron will consume 1000J in one second 
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