Avoid the jargonistic use of this word when the meaning may be obscure or ambiguous, as in normal findings and normal results. Avoid referring to physiologic saline by the obsolete phrase normal saline, which may be misinterpreted as 1 N sodium chloride. (1) Typical; usual; according to the rule or standard. (2) In bacteriology, nonimmune; untreated; denoting an animal, or the serum or substance contained therein, that has not been experimentally or naturally immunized against a microorganism or its products. (3) Denoting a solution containing 1 eq of replaceable hydrogen or hydroxyl per liter; e.g., 1 mol/L HCl is 1 n, but 1 mol/L H2SO4 is 2 n. (4) In psychiatry and psychology, denoting a developmentally appropriate level of effective functioning of personality, cognition, and affect that is satisfactory both to people and to their respective social milieu. (5) Referring to a straight line (or plane) at a right angle to another line (or plane). (6) Not diseased or having been subjected to an experimental procedure. (7) A molecular entity having an unbranched carbon chain; usually symbolized by n. [L. normalis, according to pattern]