Knowing when to use the word meter or metre depends on the location of the writer. Meter or metre both mean the same thing. The word meter, or metre, refers to the base unit for measuring length in the metric system. It can also refer to a measurement in music or poetry depending on the context.
The spelling of the word meter, with the "er" at the end, is the American English spelling of .
the word.
The spelling of the word metre, with the "re" at the end, is the British spelling of the word. They both have the same meaning.
When in England, or writing for a British audience, the word metre will be used. When in America, or writing for an American audience, the word meter will be the correct choice.
More Reference Links: http://dictionary.reference.com/browse/meter?s=t and http://dictionary.reference.com/browse/mic?s=t
