Words ending in -og/-ogue

Some nouns that end with -ogue in British English end with either -og or -ogue in American English:

analog or analogueanalogue
catalog or cataloguecatalogue
dialog or dialoguedialogue

Note that in American English, the distinctions here are somewhat fuzzy. The spelling analogue is acceptable but uncommon in American English; catalog has become the US norm, but catalogue is not uncommon; dialogue continues to be preferred over dialog. It's words such as these that make it so important for the writer to choose an acceptable spelling and stick with it!

Grammar and usage