adj. & n.
adj. 1 a existing in or caused by nature; not artificial (natural landscape). b uncultivated; wild (existing in its natural state). 2 in the course of nature; not exceptional or miraculous (died of natural causes; a natural occurrence). 3 (of human nature etc.) not surprising; to be expected (natural for her to be upset). 4 a (of a person or a person's behaviour) unaffected, easy, spontaneous. b (foll. by to) spontaneous, easy (friendliness is natural to him). 5 a (of qualities etc.) inherent; innate (a natural talent for music). b (of a person) having such qualities (a natural linguist). 6 not disguised or altered (as by make-up etc.). 7 lifelike; as if in nature (the portrait looked very natural). 8 likely by its or their nature to be such (natural enemies; the natural antithesis). 9 having a physical existence as opposed to what is spiritual, intellectual, etc. (the natural world). 10 a related by nature, out of wedlock, esp. in a specified manner (her natural son). b illegitimate (a natural child). 11 based on the innate moral sense; instinctive (natural justice). 12 Mus. a (of a note) not sharpened or flattened (B natural). b (of a scale) not containing any sharps or flats. 13 not enlightened or communicated by revelation (the natural man).
n. 1 colloq. (usu. foll. by for) a person or thing naturally suitable, adept, expert, etc. (a natural for the championship). 2 archaic a person mentally deficient from birth. 3 Mus. a a sign ( *) denoting a return to natural pitch after a sharp or a flat. b a natural note. c a white key on a piano. 4 a Cards a hand making 21 in the first deal in pontoon. b a throw of 7 or 11 at craps. 5 a pale fawn colour. natural-born having a character or position by birth. natural childbirth Med. childbirth with minimal medical or technological intervention. natural classification a scientific classification according to natural features. natural death death by age or disease, not by accident, poison, violence, etc. natural food food without preservatives etc. natural gas an inflammable mainly methane gas found in the earth's crust, not manufactured. natural historian a writer or expert on natural history. natural history 1 the study of animals or plants esp. as set forth for popular use. 2 an aggregate of the facts concerning the flora and fauna etc. of a particular place or class (a natural history of the Isle of Wight). natural key (or scale) Mus. a key or scale having no sharps or flats, i.e. C major and A minor. natural language a language that has developed naturally. natural law 1 Philos. unchanging moral principles common to all people by virtue of their nature as human beings. 2 a correct statement of an invariable sequence between specified conditions and a specified phenomenon. 3 the laws of nature; regularity in nature (where they saw chance, we see natural law). natural life the duration of one's life on earth. natural logarithm see LOGARITHM. natural magic magic involving the supposed invocation of impersonal spirits. natural note Mus. a note that is neither sharp nor flat. natural numbers the integers 1, 2, 3, etc. natural philosopher archaic a physicist. natural philosophy archaic physics. natural religion a religion based on reason (opp. revealed religion); deism. natural resources materials or conditions occurring in nature and capable of economic exploitation. natural science the sciences used in the study of the physical world, e.g. physics, chemistry, geology, biology, botany. natural selection the Darwinian theory of the survival and propagation of organisms best adapted to their environment. natural theology the knowledge of God as gained by the light of natural reason. natural uranium unenriched uranium. natural virtues Philos. justice, prudence, temperance, fortitude. natural year the time taken by one revolution of the earth round the sun, 365 days 5 hours 48 minutes. naturalness n.
[ ME f. OF naturel f. L naturalis (as NATURE) ]