noun
also oc·tette (ˈ)äk|tet, usu -ed.+V
( -s )
Etymology: octa- + -et or -ette; translation of Italian ottetto
1.
a. : a musical composition for eight parts (as eight instruments or voices)
b. : a group of eight singers or players in joint performance
2. : octave 2b
3. : a group of eight electrons in the outer valence shell of an atom that are considered to constitute a stable arrangement and to be present in pairs which may or may not be shared with another atom — compare covalence , lewis-langmuir theory