| 释义 | pe·ris·sad \pəˈrisəd, -iˌsad\ noun
 (-s)
 Etymology: Greek perissos beyond the regular number or size, superfluous, excessive, uneven (from peri around, beyond) + English -ad
 1. obsolete  : an element or radical of odd valence
 2.  : an element of odd atomic number — contrasted with artiad
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