Octet, octave, ottava all mean 8-line verse or stanza (section of a larger poem). There are also specific types of verse, such as triolet, which is an 8-line poem style from Medieval France in which...
The default term for an eight-line stanza is an octet. An octet which is rimed ABABABCC is called ottava rima. Ottava rima was used for several important late Tudor translations (particularly...