1》 reasoning conducted or assessed according to strict principles of validity.
↘the quality of being justifiable by reason.
↘( the ~ of ) the course of action following as a necessary consequence of.
2》 a system or set of principles underlying the arrangements of elements in a computer or electronic device so as to perform a specified task.
ME: via OFr. logique and late L. ~a from Gk logikē (tekhnē) '(art) of reason'.