The modern numerical digit 0 is usually written as a circle or ellipse. Traditionally, many print typefaces made the capital letter O more rounded than the narrower, elliptical digit 0. Typewriters originally made no distinction in shape between O and 0; some models did not even have a separate key for the digit 0. The distinction came into prominence on modern character displays.
0, zero, "oh" (/oʊ/), nought, naught, nil
Zeroth, noughth, 0th
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०
零, 〇
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๐
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