As nouns the difference between australian and thickhead

is that australian is a person from the country of australia or of australian descent while thickhead is someone stupid.

As an adjective australian

is of, from, or pertaining to australia, the australian people or australian languages.

As nouns the difference between songbird and thickhead

is that songbird is a bird having a melodious song or call while thickhead is someone stupid.

As nouns the difference between genus and thickhead

is that genus is a rank in the classification of organisms, below family and above species; a taxon at that rank while thickhead is someone stupid.

As a proper noun pachycephala

is .

As a noun thickhead is

someone stupid.

As an adjective biological

is of or relating to biology.

As a proper noun bilin is

.

As nouns the difference between pigment and bilin

is that pigment is any color in plant or animal cells while bilin is any of various biological pigments formed in many organisms as a metabolic product of certain porphyrins.

As a verb pigment

is to add color or pigment to something.

As nouns the difference between organism and bilin

is that organism is a discrete and complete living thing, such as animal, plant, fungus or microorganism while bilin is any of various biological pigments formed in many organisms as a metabolic product of certain porphyrins.

As an adjective metabolic

is of or pertaining to metamorphosis; pertaining to, or involving, change.

As a proper noun bilin is

.

As a noun product

is a commodity offered for sale.

As a proper noun bilin is

.

As nouns the difference between porphyrin and bilin

is that porphyrin is any of a class of heterocyclic compounds containing four pyrrole rings arranged in a square; they are important in biochemistry in a form with a metal atom in the central cavity (hemoglobin with iron, chlorophyll with magnesium, etc.) while bilin is any of various biological pigments formed in many organisms as a metabolic product of certain porphyrins.