octad

American  

[ok-tad] / ˈɒk tæd /

noun

1. a group or series of eight.

2. Chemistry. an element, atom, or group having a valence of eight.

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octad British  

/ ˈɒktæd /

noun

1. a group or series of eight

2. chem an element or group with a valency of eight

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Other Word Forms

• octadic adjective

Etymology

Origin of octad

1835–45; < Greek oktad- (stem of oktás ) group of eight, equivalent to okt- oct- + -ad -ad ¹

Example Sentences

The number Eight, or the octad, is the first cube, that is to say, squared in all senses, as a die, proceeding from its base two, an even number; so is man four-square, or perfect.

From Project Gutenberg