naked eye

1. Sight unassisted by an instrument such as a microscope or telescope. For example, These insects are too small to be seen with the naked eye. This expression was first recorded in 1664.

Example Sentences

No longer visible to the naked eye and too big to realistically excavate very quickly, they made narrow boreholes to take samples of the material from the features.

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But the opposite, reflective face bears an image incised in finely engraved lines that under normal conditions is virtually imperceptible to the naked eye.

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In Major League Soccer, offside decisions are made with the naked eye.

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Most of his passes are completely devoid of wobble, at least to the naked eye.

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The darker the skies, the more visible the meteors will be to the naked eye.

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