perissad

noun

pe·​ris·​sad

pəˈrisəd,

-iˌsad

plural -s

1

obsolete : an element or radical of odd valence

2

: an element of odd atomic number

—contrasted with artiad

Word History

Etymology

Greek perissos beyond the regular number or size, superfluous, excessive, uneven (from peri around, beyond) + English -ad

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