unassuming

As adjectives the difference between courteous and unassuming

is that courteous is showing regard or thought for others; especially, displaying good manners or etiquette while unassuming is modest and having no pretensions or ostentation.

As adjectives the difference between gentle and unassuming

is that gentle is tender and amiable; of a considerate or kindly disposition while unassuming is modest and having no pretensions or ostentation.

As a verb gentle

is to become gentle.

As a noun gentle

is a person of high birth.

As adjectives the difference between demure and unassuming

is that demure is quiet, modest, reserved, sober, or serious while unassuming is modest and having no pretensions or ostentation.

As a verb demure

is to look demurely.

As adjectives the difference between unassuming and relaxed

is that unassuming is modest and having no pretensions or ostentation while relaxed is having an easy-going mood or temperament.

As a verb relaxed is

(relax).

As adjectives the difference between unassuming and simple

is that unassuming is modest and having no pretensions or ostentation while simple is uncomplicated; taken by itself, with nothing added.

As a noun simple is

(medicine) a preparation made from one plant, as opposed to something made from more than one plant.

As a verb simple is

(transitive|intransitive|archaic) to gather simples, ie, medicinal herbs.

As adjectives the difference between unassuming and robust

is that unassuming is modest and having no pretensions or ostentation while robust is evincing strength; indicating vigorous health; strong; sinewy; muscular; vigorous; sound; as, a robust body; robust youth; robust health.

Prim is a related term of unassuming.

As a noun prim

is prime (the first note or tone of a musical scale).

As an adjective unassuming is

modest and having no pretensions or ostentation.

As adjectives the difference between unassuming and considerate

is that unassuming is modest and having no pretensions or ostentation while considerate is consciously thoughtful and observant (often of other people); caring.

As adjectives the difference between unassuming and unpretentious

is that unassuming is modest and having no pretensions or ostentation while unpretentious is simple, humble, not pretentious, plain.