Definition of: natural

(nach′ər·əl) adjective
1. Of or pertaining to one's nature or constitution; innate; inborn; also, indigenous; native.
2. Of or pertaining to a particular nature; derived from nature; hence, exhibiting kindly feeling or affection.
3. Of or pertaining to nature; belonging or pertaining to the existing order of things: natural law; normal.
4. Coming within common experience; having to do with objects in the order of nature: opposed to supernatural.
5. Not forced or artificial; without affectation or exaggeration; lifelike.
6. Produced by nature; not artificial: a natural bridge.
7. Connected by ties of consanguinity; being such by birth: a natural brother.
8. Belonging to the inferior nature; not spiritual; animal.
9. Born out of wedlock; illegitimate.
10. Music Not sharped nor flatted: G natural; specifically, denoting the key of C, which is without flats or sharps in the signature.
11. Math. Designating an actual number in contradistinction to a logarithm: a natural sine, natural cosine, natural tangent, etc. See synonyms under INHERENT, NATIVE, NORMAL, PHYSICAL, RADICAL.
—noun
1. Music a A note on a line or a space that is affected by neither a sharp nor a flat. b A character which acts upon a sharped degree of the staff as a flat and upon a flatted degree as a sharp.
2. In keyboard musical instruments, a white key.
3. One born without the usual powers of reason or understanding; a born fool.
4. Colloq. A person or thing admirably suited for some purpose, or obviously destined for success. [<F naturel <L naturalis <natura nature]
—nat′u·ral·ness noun