Parallelism

from Greek: parallelos “side-by-side”

Similarity of structure in a pair or series of related words, phrases, or clauses.

Examples:

Parallelism of words:

She tried to make her pastry fluffy, sweet, and delicate.

Parallelism of phrases:

Singing a song or writing a poem is joyous.

Parallelism of clauses:

Perch are inexpensive; cod are cheap; trout are abundant; but salmon are best.