positive (adj.)

early 14c., originally a legal term meaning "formally laid down, decreed or legislated by authority" (opposed to natural),  from Old French positif (13c.) and directly from Latin positivus "settled by agreement, positive" (opposed to naturalis "natural"), from positus, past participle of ponere "put, place" (see position (n.)).

The sense of "absolute" is from mid-15c. Meaning in philosophy of "dealing only with facts" is from 1590s. Sense broadened to "expressed without qualification" (1590s), then, of persons, "confident in opinion" (1660s). The meaning "possessing definite characters of its own" is by 1610s. The mathematical use for "greater than zero" is by 1704. Psychological sense of "concentrating on what is constructive and good" is recorded from 1916. Positive thinking is attested from 1953. The sense in electricity is from 1755.  

There are probably no two bodies differing in nature which are not capable of exhibiting electrical phaenomena, either by contact, pressure, or friction ; but the first substances in which the property was observed, were vitreous and resinous bodies ; and hence the different states were called states of resinous and vitreous electricity ; and resinous bodies bear the same relation to flint glass, as silk. The terms, negative and positive electricity, have been likewise adopted, on the idea, that the phaenomena depend upon a peculiar subtile fluid, which becomes in excess in the vitreous, and deficient in the resinous bodies ; and which is conceived by its motion and transfer, to produce the electrical phaenomena. [Sir Humphry Davy, "Elements of Chemical Philosophy," London, 1812]

positive (n.)

1520s, originally in grammar, from positive (adj.). Sense of "that which can be affirmed, reality" is from 1610s. Sense in photography (opposite of negative (n.)) is by 1853.

updated on September 11, 2020

Definitions of positive from WordNet
positive (adj.)
persuaded of; very sure;
I am positive he is lying
Synonyms: convinced / confident
positive (adj.)
characterized by or displaying affirmation or acceptance or certainty etc.;
a positive attitude
the reviews were all positive
a positive benefit
a positive demand
positive (adj.)
involving advantage or good;
a plus (or positive) factor
Synonyms: plus
positive (adj.)
indicating existence or presence of a suspected condition or pathogen;
a positive pregnancy test
Synonyms: confirming
positive (adj.)
formally laid down or imposed;
positive laws
Synonyms: prescribed
positive (adj.)
impossible to deny or disprove;
proof positive
positive (adj.)
of or relating to positivism;
positive philosophy
Synonyms: positivist / positivistic
positive (adj.)
reckoned, situated or tending in the direction which naturally or arbitrarily is taken to indicate increase or progress or onward motion;
positive increase in graduating students
positive (adj.)
greater than zero;
positive numbers
positive (adj.)
having a positive charge;
protons are positive
Synonyms: electropositive / positively charged
positive (adj.)
marked by excessive confidence;
the less he knows the more positive he gets
Synonyms: cocksure / overconfident
positive (n.)
the primary form of an adjective or adverb; denotes a quality without qualification, comparison, or relation to increase or diminution;
Synonyms: positive degree
positive (n.)
a film showing a photographic image whose tones correspond to those of the original subject;
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