Definition of law. 1  1a (1) : a binding custom or practice of a community : a rule of conduct or action prescribed (see prescribe 1a) or formally recognized as binding or enforced by a controlling authority (2) : the whole body of such customs, practices, or rules The courts exist to uphold, interpret, and apply the law.
cation-anion balance. the balance in serum or plasma between the anions and cations must equilibrate near to the level of 155 mEq/l. Estimation of any imbalance, usually by chloride and bicarbonate measurement, is basic to any determination of acid-base abnormality. cation channels.
An easy way to remember that cations are positive ions is by replacing the 't' in 'cation' with a positive sign, +. Instead of writing cation, you would write ca+ion. The positive sign bears enough likeness to a 't' to be read as cation, yet it reminds you of the definition!