[nawr-muh l]
See more synonyms for normal on
  1. conforming to the standard or the common type; usual; not abnormal; regular; natural.
  2. serving to establish a standard.
  3. Psychology.
    1. approximately average in any psychological trait, as intelligence, personality, or emotional adjustment.
    2. free from any mental disorder; sane.
  4. Biology, Medicine/Medical.
    1. free from any infection or other form of disease or malformation, or from experimental therapy or manipulation.
    2. of natural occurrence.
  5. Mathematics.
    1. being at right angles, as a line; perpendicular.
    2. of the nature of or pertaining to a mathematical normal.
    3. (of an orthogonal system of real functions) defined so that the integral of the square of the absolute value of any function is 1.
    4. (of a topological space) having the property that corresponding to every pair of disjoint closed sets are two disjoint open sets, each containing one of the closed sets.
    5. (of a subgroup) having the property that the same set of elements results when all the elements of the subgroup are operated on consistently on the left and consistently on the right by any element of the group; invariant.
  6. Chemistry.
    1. (of a solution) containing one equivalent weight of the constituent in question in one liter of solution.
    2. pertaining to an aliphatic hydrocarbon having a straight unbranched carbon chain, each carbon atom of which is joined to no more than two other carbon atoms.
    3. of or relating to a neutral salt in which any replaceable hydroxyl groups or hydrogen atoms have been replaced by other groups or atoms, as sodium sulfate, Na2SO4.
  1. the average or mean: Production may fall below normal.
  2. the standard or type.
  3. Mathematics.
    1. a perpendicular line or plane, especially one perpendicular to a tangent line of a curve, or a tangent plane of a surface, at the point of contact.
    2. the portion of this perpendicular line included between its point of contact with the curve and the x-axis.

Origin of normal

1520–30; < Latin normālis made according to a carpenter's square, equivalent to norm(a) (see norm) + -ālis -al1
Related formsnor·mal·i·ty, nor·mal·ness, nounan·ti·nor·mal, adjectivean·ti·nor·mal·ness, nounan·ti·nor·mal·i·ty, nounhalf-nor·mal, adjectivehalf-nor·mal·ly, adverbhy·per·nor·mal, adjectivehy·per·nor·mal·ly, adverbhy·per·nor·mal·ness, nounhy·per·nor·mal·i·ty, nounnon·nor·mal, adjectivenon·nor·mal·ly, adverbnon·nor·mal·ness, nounnon·nor·mal·i·ty, noun, plural non·nor·mal·i·ties.o·ver·nor·mal, adjectiveo·ver·nor·mal·ly, adverbo·ver·nor·mal·i·ty, nounqua·si-nor·mal, adjectivequa·si-nor·mal·ly, adverbsem·i·nor·mal, adjectivesem·i·nor·mal·ly, adverbsem·i·nor·mal·ness, nounsem·i·nor·mal·i·ty, nountrans·nor·mal, adjectivetrans·nor·mal·ly, adverbun·nor·mal, adjectiveun·nor·mal·ly, adverbun·nor·mal·ness, noun


[nawr-muh l]
  1. a city in central Illinois. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for normal

Contemporary Examples of normal

Historical Examples of normal

British Dictionary definitions for normal


  1. usual; regular; common; typicalthe normal way of doing it; the normal level
  2. constituting a standardif we take this as normal
  3. psychol
    1. being within certain limits of intelligence, educational success or ability, etc
    2. conforming to the conventions of one's group
  4. biology med (of laboratory animals) maintained in a natural state for purposes of comparison with animals treated with drugs, etc
  5. chem (of a solution) containing a number of grams equal to the equivalent weight of the solute in each litre of solventSymbol: N
  6. chem denoting a straight-chain hydrocarbon: a normal alkane . Prefix: n-, e.g. n- octane
  7. geometry another word for perpendicular (def. 1)
  1. the usual, average, or typical state, degree, form, etc
  2. anything that is normal
  3. geometry a line or plane perpendicular to another line or plane or to the tangent of a curved line or plane at the point of contact
Derived Formsnormality (nɔːˈmælɪtɪ) or esp US normalcy, noun

Word Origin for normal

C16: from Latin normālis conforming to the carpenter's square, from norma norm
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for normal

c.1500, "typical, common;" 1640s, "standing at a right angle," from Late Latin normalis "in conformity with rule, normal," from Latin normalis "made according to a carpenter's square," from norma "rule, pattern," literally "carpenter's square" (see norm). Meaning "conforming to common standards, usual" is from 1828, but probably older than the record [Barnhart].

As a noun meaning "usual state or condition," from 1890. Sense of "normal person or thing" is from 1894. Normal school (1834) is from French école normale (1794), a republican foundation. The city of Normal, Illinois, U.S., was named 1857 for the normal school established there.

Online Etymology Dictionary, © 2010 Douglas Harper

normal in Medicine


  1. Conforming with, adhering to, or constituting a norm, standard, pattern, level, or type; typical.
  2. Functioning or occurring in a natural way; lacking observable abnormalities or deficiencies.
  3. Occurring naturally and not because of disease, inoculation, or any experimental treatment. Used of immunity.
  4. Of, relating to, or being a solution having one gram equivalent weight of solute per liter of solution.
  5. Of, relating to, or being an aliphatic hydrocarbon having a straight and unbranched chain of carbon atoms.
  6. Of, relating to, or characterized by average intelligence or development.
  1. The usual or the expected state, form, amount, or degree.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.