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1st, 2nd, 3rd, ... well - I've never heard about "the 0-st". Enumerating starting with zero seems to have come in vogue with C,

There's been a Zero Church Street in Cambridge, Mass., for a good deal longer than there's been a C programming language. Blame the mathematicians.

The Indian calendars use a large number of counting years. Some of those start with 0, others with 1. This even predates Cambridge, Mass.. dik