noun

• (uncountable) A method of human thought that involves thinking in a linear, step-by-step manner about how a problem can be solved. Logic is the basis of many principles including the scientific method.
• (philosophy, logic) The study of the principles and criteria of valid inference and demonstration.
  "An old tradition has it that there are two branches of logic: deductive logic and inductive logic. More recently, the differences between these disciplines have become so marked that most people nowadays use "logic" to mean deductive logic, reserving terms like "confirmation theory" for at least some of what used to be called inductive logic. I shall follow the more recent practice, and shall construe "philosophy of logic" as "philosophy of deductive logic"."
• (uncountable, mathematics) The mathematical study of relationships between rigorously defined concepts and of mathematical proof of statements.
• (countable, mathematics) A formal or informal language together with a deductive system or a model-theoretic semantics.

verb

• (intransitive, derogatory) To engage in excessive or inappropriate application of logic.
  "Nay, is not the author himself "logicking" against logic, from the beginning of his book to the end ?"
• (transitive) To apply logical reasoning to.
  "He logicked that one out. He snuck into Haiti and scored herbs to rev him and calm him."
• (transitive) To overcome by logical argument.
  "If things had gone as usual this night, if Kit had not logicked her into agreement, then she probably would have opened the door tonight."