arrowworm: any worm of the Chaetognatha; transparent marine worm with horizontal lateral and caudal fins and a row of movable curved spines at each side of the mouth
invertebrate: any animal lacking a backbone or notochord; the term is not used as a scientific classification
power of appointment: authority given (in a will or deed) by a donor to a donee to appoint the beneficiaries of the donor's property