Two quartets

• One's pawns on a chessboard, e.g
• Bits in a byte, e.g
• Eight-PArt group
• Series of eight
• Ennead minus one
• Santa's reindeer, sans Rudolph
• Rowing team quorum
• Santa's reindeer team, e.g.
• Rowing team, e.g

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Octad \Oc"tad\, n. [Gr. ?, ?, the number eight.] (Chem.) An atom or radical which has a valence of eight, or is octavalent. A group of eight things.