1) Based on individual will or choice rather than by reason or necessity.
M.E., from O.Fr. arbitraire or directly from L. arbitrarius "depending on the will, uncertain," from → ad- "to" + baetere "to come, go."
Fr.: constante arbitraire
A constant quantity in → equations which takes various values but which remains unaffected by the changes in the values of the → variables of the equation. Most → differential equations have more than one → solution. In general, the number of arbitrary constants of an ordinary differential equation is given by the → order of the highest → derivative.