blackhead

As nouns the difference between blackhead and blockhead

is that blackhead is a comedo, a skin blemish, a type of acne vulgaris, where a pore becomes clogged with a dark, hard, cheesy keratin-filled substance forming a hard black "head" on the skin's surface while blockhead is a stupid person.

As nouns the difference between blackhead and backhead

is that blackhead is (medicine) a comedo, a skin blemish, a type of acne vulgaris, where a pore becomes clogged with a dark, hard, cheesy keratin-filled substance forming a hard black "head" on the skin's surface while backhead is the wall of a steam locomotive's firebox, located in the cab, where the controls are mounted.

As nouns the difference between blackhead and blacklead

is that blackhead is (medicine) a comedo, a skin blemish, a type of acne vulgaris, where a pore becomes clogged with a dark, hard, cheesy keratin-filled substance forming a hard black "head" on the skin's surface while blacklead is .

As a verb blacklead is

to cover, treat or polish with graphite.

As nouns the difference between taxonomy and blackhead

is that taxonomy is the science or the technique used to make a classification while blackhead is a comedo, a skin blemish, a type of acne vulgaris, where a pore becomes clogged with a dark, hard, cheesy keratin-filled substance forming a hard black "head" on the skin's surface.