Second

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Second

1. See: Second mortgage.

2. See: Second round.
References in periodicals archive ?
Uretmen et al found 480 seconds of arc or better was present in 21.
It was also claimed that the optometrist did not undertake retinoscopy with a cycloplegic agent in circumstances where the examination indicated a visual acuity of 3/9, stereo acuity was 200 seconds of arc, there was limited cooperation from the child patient, and the reason for the examination was she had been squinting and closing her eyes when watching television.
5x20 = 30 seconds of arc, which is impossible for most human eyes to see.