As adjectives the difference between arctic and circumarctic

is that arctic is while circumarctic is lying around the arctic.

As a proper noun arctic

is .

As a noun arctic

is .

As nouns the difference between cephalopod and counterillumination

is that cephalopod is any mollusc, of the class Cephalopoda, which includes squid, cuttlefish, octopus, nautiloids etc while counterillumination is a behaviour, found in some cephalopods etc., in which bioluminescence is used to provide camouflage when viewed from below.

As nouns the difference between bioluminescence and counterillumination

is that bioluminescence is (biology|biochemistry) the emission of light by a living organism (such as a firefly) while counterillumination is (biology) a behaviour, found in some cephalopods etc, in which bioluminescence is used to provide camouflage when viewed from below.

As nouns the difference between camouflage and counterillumination

is that camouflage is camouflage while counterillumination is (biology) a behaviour, found in some cephalopods etc, in which bioluminescence is used to provide camouflage when viewed from below.

As nouns the difference between bacterium and chemosymbiosis

is that bacterium is (microbiology) a single celled organism with no nucleus while chemosymbiosis is (biology) a form of symbiosis in which a bacterium provides chemically-derived energy and nutrients, often via the oxidation of hydrogen sulfide, to a higher organism.

As nouns the difference between energy and chemosymbiosis

is that energy is the impetus behind all motion and all activity while chemosymbiosis is (biology) a form of symbiosis in which a bacterium provides chemically-derived energy and nutrients, often via the oxidation of hydrogen sulfide, to a higher organism.

As nouns the difference between nutrient and chemosymbiosis

is that nutrient is a source of nourishment, such as food, that can be metabolized by an organism to give energy and build tissue while chemosymbiosis is (biology) a form of symbiosis in which a bacterium provides chemically-derived energy and nutrients, often via the oxidation of hydrogen sulfide, to a higher organism.

As an adjective nutrient

is providing nourishment.

As nouns the difference between oxidation and chemosymbiosis

is that oxidation is oxidation, a reaction in which the atoms of an element lose electrons while chemosymbiosis is (biology) a form of symbiosis in which a bacterium provides chemically-derived energy and nutrients, often via the oxidation of hydrogen sulfide, to a higher organism.

As a noun chemosynthesis

is the production of carbohydrates and other compounds from simple compounds such as carbon dioxide, using the oxidation of chemical nutrients as a source of energy rather than sunlight; it is limited to certain bacteria and fungi.

As an adjective chemosynthetic is

that utilizes chemosynthesis.

As nouns the difference between carbohydrate and chitooligomer

is that carbohydrate is a sugar, starch, or cellulose that is a food source of energy for an animal or plant; a saccharide while chitooligomer is a class of carbohydrate oligomer derived from chitin; chitooligosaccharide.