zoo-, zoa-, zo-, -zoic, -zoid, -zoite, -zoal, -zonal, -zooid, -zoon, -zoa, -zoan

An organism that inhabits the middle depths of the sea: The nectozooids are neither the benthos, which are animals and plants living on the bottom of a sea or lake, nor the plankton or the animal and plant life, mostly microscopic, which generally floats and drifts near the surface of a lake, river, or sea.

A defensive zooid in a hydroid or siphohonophore, bearing many stinging cells: The nematozooids have organs for protection which are found in the siphohonophores which belong to the "Siphonophora", an order of marine hydrozoan coelentrates, both medusoid and polypoid individuals joining to form free-swimming colonies, often large and brightly colored, with highly toxic stings, including the Portuguese man-of-war.

Concerning the period of geological time from the end of the Mesozoic to the present: Susan read about the Cenozoic era, instead of the outdated Neozoic period, which refers to the last 68 million years of the Earth's history.

An individual that develops from an egg and reproduces by budding: An oozooid is the compound tunicate larva that has been sexually produced, and that, by budding, forms blastozooids.

Oozooid is used with reference to colonies of tunicates, for example sea-squirts, or similar organisms.

Relating to the geologic era extending from the end of the Precambrian to the beginning of the Mesozoic: The Paleozoic period, formally termed "Primary", dates from about 542 to 250 million years ago, from the era of trilobites to those of the reptiles.

The study of the distribution of fossil animal remains: Janet studied paleobiogeography and wanted to specialize in paleozoogeography, which dealt with the dispersion or of animals in past geologic times.

Concerning paleozoology, or the research of ancient animal life: Greg found a rock with a fossil of an insect, and then he needed to find a book about paleozoological remains to find out more about his discovery!

A subdivision of paleontology that is the study of fossil animals: Mandy was certainly interested in petrified remains of the geological past and decided to specialize in paleozoology and learn more about prehistoric animals and their evolution.

Relating to a disease involving many kinds of animals: Similar to a pandemic, which involves only people all over the world, a panzootic outbreak of an infectious disorder affects a very large number of animals, and usually more than just one species, and spreads across huge regions, like a continent, or even across the whole world.

A group of organisms with many cells which are less-specialized than the Metazoa: The rarely used taxon of the animal kingdom, termed Parazoa, was established at one time to contain the phylum Porifera, in distinction from the Eumetazoa containing all other metazoan animals.

A member of the phylum Porifera, the sponges: A parazoon is a multicellular invertebrate that has a body filled with channels and pores which permit water to flow through them and which consist of jelly-like mesohyl inserted between two delicate layers of cells.

An animal that feeds on decaying or dead tissue: Vultures, a type a bird, is a phagozoite that maintains its existence by consuming carrion, which is lifeless or putrefying flesh.

The age of geologic time, beginning 570 million years ago and lasting up to the present: The Phanerozoic Eon consists of the Paleozoic, Mesozoic, and Cenozoic eras which are marked by an abundance of fossil evidence of life, especially higher forms, in the corresponding rocks.

An exoerythrocytic tissue stage of malaria found in the later stage of infection: Phanerozoites develop chiefly by reinfection of the liver by merozoites produced by a blood infection (not found in falciparum [tropical parasitic disease] malaria).

The tissues found in the subsequent stages are different to the primary exoerythrocytic stages (cryptozoite and metacryptozoite generations).

A zooid that attaches itself to the back of its parent: While being fixated to its progenitor, the phorozoon carries and nourishes another type at the same time which is called the "gonozooid" that subsequently breaks free to reproduce sexually.

The nonsexual phase or generation of a phorozoon involves an alternation of generations or sequence of reproductive modes.