As nouns the difference between sports and fitness

is that sports is plural of lang=en while fitness is the condition of being fit, suitable or appropriate.

As a verb sports

is third-person singular of sport.

As adjectives the difference between cognizant and rational

is that cognizant is aware; fully informed; having understanding while rational is capable of reasoning.

As a noun rational is

(mathematics) a rational number: a number that can be expressed as the quotient of two integers.

As nouns the difference between domain and universe

is that domain is a geographic area owned or controlled by a single person or organization while universe is the sum of everything that exists in the cosmos, including time and space itself; same as the Universe.

As a proper noun Universe is

the sum of everything that exists in the cosmos, including time and space itself.

As adjectives the difference between flighty and ditzy

is that flighty is given to unplanned and silly ideas or actions while ditzy is silly or scatterbrained, usually of a woman.

As nouns the difference between book and periodical

is that book is a collection of sheets of paper bound together to hinge at one edge, containing printed or written material, pictures, etc while periodical is a publication issued regularly, but less frequently than daily.

As a verb book

is to reserve (something) for future use.

As an adjective periodical is

periodic.

As nouns the difference between standard and premium

is that standard is a principle or example or measure used for comparison while premium is a prize or award.

As adjectives the difference between standard and premium

is that standard is falling within an accepted range of size, amount, power, quality, etc while premium is superior in quality; higher in price or value.

As adjectives the difference between royal and deluxe

is that royal is (used in terms of address or reference to members of a royal family) while deluxe is being very fine in quality or luxurious.

As a proper noun royal

is .

As a noun royal

is (soccer) someone connected with , as a fan, player, coach etc.

As nouns the difference between tiger and numbat

is that tiger is Panthera tigris, a large predatory mammal of the cat family, indigenous to Asia while numbat is a small marsupial carnivore, Myrmecobius fasciatus, endemic to western Australia that eats almost exclusively termites.

As a proper noun Tiger

is a town in Georgia.

As nouns the difference between koala and numbat

is that koala is a tree-dwelling marsupial that resembles a small bear with a broad head, large ears and sharp claws, mainly found in eastern Australia while numbat is a small marsupial carnivore, Myrmecobius fasciatus, endemic to western Australia that eats almost exclusively termites.

As an adverb then

is (label) at that time.

As an adjective then

is being so at that time.

As a noun then

is that time.

As a conjunction then

is .

As a determiner was is

your (plural and polite).