acro-, acr-

Organisms floating extremely high in the air: For his class at school, Jim read about acroplankton that were tiny lifeforms that drifted in the air and were transported by the wind.

A large aquatic plant that floats freely on the surface of the water: When Max was standing at the side of the Pacific Ocean, he viewed an acropleustophyte entangled in an old fish net and drifting along on top the water.

Concerning aquatic plants that drift freely on top of water: Along the beach of the ocean, Jane saw a lot of acropleustophytic organisms laking locomotion floating among the rocky areas.

1. The upper surface of the whole foot: The thick boots that Jack wore covered the acroppodia of his feet to protect them from the cold winter weather.
2. An elevated pedestal supporting a statue: The acropdium with a marble statuette on top had been placed in the center of the room in the museum.

The citadel of Athens: The Acropolis is the famous citadel of Athens including the Parthenon, the Erechtheum, and other distinguished edifices, many of them dating from the 5th century BC.

The Parthenon was the chief temple of the goddess Athena built on the acropolis at Athens between 447 and 432 B.C. and considered a supreme example of Doric architecture.

A promontory, usually a fortified citadel, that created the center of a Grecian city at the top or on a hill: Acropolises apply to very old Greek settlements which were built high up on a hill and served as forts, centers for religious activities, and finally as a cultural core of larger cities.

One famous acropolis is the ancient city of Athens.

Inflammation of the prepuce (foreskin): Acroposthitis can occur when the folds of the skin that cover the penis or clitoris become quite irritated and start to burn or sting.

An ailment with pustular (small circumscribed elevation of the skin, containing purulent material) eruptions of the hands and feet: Acropustulosis is often a form of psoriasis, which is disease that causes dry red patches on the skin.

In botany, a pulpy berry resulting from the union of an ovary and a calyx: In her biology class Judy learned that acrosarc was important in the reproduction and growth of plants.

A hard, thickened skin condition of the toes and the fingers; sclerodactyly: Acroscleroderma can affect the digits of the limbs as well as the neck, the face, and especially the nose causing a tightness and stiffness of the parts involved.

A stiffness and tightness of the skin of the fingers, with atrophy of the soft tissue and osteoporosis of the distal phalanges of the hands and feet: Acrosclerosis is a disease of a limited form of progressive systemic sclerosis occurring with Raynaud’s phenomenon.

In botany, referring to a part of a plant facing upwards towards the apex (tip) of the axis on which something is borne or carried: Mr. Root, the biology teacher, told his students to go out and take photos of acroscopic leaves or branches to show the class the next day.

A structure at the end of a sperm cell that releases enzymes aiding in the penetration of the cell membrane of an egg: The acrosome enables the sperm to enter the egg for fertilization.

The acrosome is the body at the apex of a spermatozoon.

The acrosome can also be described as the cytoplasmic cap-like structure on the front of a spermatozoan (sperm; a mature male germ cell).

The first shoot at the end of a germinating seed: An acrospire appears from the plumule of a sprouting grain seed.

To put forth or give life to the first sprout: Chuck watched the spiral primary buds of his germinating grain seeds acrospire from the soil in his field.