pen·nat·u·la \pəˈnachələ\noun Etymology: New Latin, from Late Latin, feminine of pennatulus winged, from Latin pennatus winged + -ulus -ule 1.capitalized: a common genus (the type of the family Pennatulidae) of sea pens 2.pluralpennatu·lae\-chəˌlē\orpennatulas: sea pen • pen·nat·u·lid\-lə̇d\adjective or noun