Dictionary of Ichthyology
This dictionary of ichthyology contains specialist terms used in the teaching of undergraduate students. The terms are arranged alphabetically for ease of reference.
In addition to ichthyology, terms from hydrobiology, zoology, anatomy, fish farming and other related disciplines are included.
Where terms have different interpretations, we have assigned the most common interpretation in our view.
This dictionary is constantly being added to and modified.
If you do not agree with the above interpretation of the Terms, please explain your understanding in the comments to these Terms.
We invite you to participate in the development of a modern ichthyological vocabulary.
We will consider any criticism and take it into account when describing dictionary terms.
Omnivorous fish
Fish diet which includes a wide variety of organisms (carp, crucian carp, tench, roach, Rudd, Barbus..
Omul
Omul (Coregonus autumnalis) is a passage fish of the whitefish family. The mouth is terminal, with 3..
Oncorhynchus masou
Oncorhynchus masou is a passage fish of the Pacific salmon genus. It is up to 70 cm long and weighs ..
One-time spawning
One-time spawning - eggs are laid all at once, in one go, in a short period of time (whitefish, salm..
Ontogeny
From Ancient Greek ὤν, Latin on > gen. ὄντος, ontos "being" + γένεσις, genesis "origin".Ontogeny ..
Open-bellied fishes
Open-bellied fish are fish whose swim bladder is connected by a duct to the intestine. Removal of ga..
Ophidiiformes
Ophidiiformes is a genus of bony fishes. Previously belonged to the cod fishes. Fish with an elongat..
Organs of electrical perception
Electrical perception organs are a cluster of sensitive cells (electroreceptors) that perceive magne..
Organs of touch
The organs of touch are represented by tactile corpuscles (clusters of sensory cells) scattered over..
Organs of vision
Organs of vision - have a typical vertebrate structure. Distinctive features of the fish eye are a f..
Osmoregulation
From Greek osmos push, pressure and Latin regulo directing.Osmoregulation - physiological processes ..
Osteichthyes
Osteichthyes is a class of vertebrates. Size from 0.7 cm to 6-7 m, mass up to 1.5 tons. The body is ..
Ovaries
The ovaries are the female reproductive organs in which eggs are formed and mature. In most fish, th..
Overgrowth
Overgrowth - mass development of aquatic vegetation in a water body, which eventually ends in waterl..
Overripe caviar
Overripe caviar are caused by a long delay in the female's cavity due to the lack of necessary envir..