Zippo vs. zippo
Wrong: He flicked open his zippo and lit a stogie.
Right: He flicked open his Zippo and lit a stogie.
Wrong: We went for it all, but we ended up with Zippo.
Right: We went for it all, but we ended up with zippo.
Zippo is a registered trademark for a brand of cigarette lighter. If you’re referring to the lighter, it should be capitalized. Conversely, if you mean zip, zilch, zero, nada, goose egg—as in nothing—then it would be lower-case zippo. You might request a Zippo but get zippo instead.
Xray vs. X-ray
Wrong: He went in for xrays of his wrist.
Right: He went in for x-rays of his wrist.
X-rays is properly written with a hyphen or as two words (x rays), but never as one word (xrays).
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