verb

• (intransitive) To move on the feet by alternately setting each foot (or pair or group of feet, in the case of animals with four or more feet) forward, with at least one foot on the ground at all times. Compare run.
  "To walk briskly for an hour every day is to keep fit."
• (intransitive, colloquial, law) To "walk free", i.e. to win, or avoid, a criminal court case, particularly when actually guilty.
  "If you can’t present a better case, that robber is going to walk."
• (intransitive, colloquial, euphemistic) Of an object, to go missing or be stolen.
  "If you leave your wallet lying around, it’s going to walk."
• (intransitive, cricket, of a batsman) To walk off the field, as if given out, after the fielding side appeals and before the umpire has ruled; done as a matter of sportsmanship when the batsman believes he is out.

noun

• (sports) An Olympic Games track event requiring that the heel of the leading foot touch the ground before the toe of the trailing foot leaves the ground.
• (figurative) A person's conduct or course in life.
  "Men like Stuart who had no desire to extol Coleridge's virtues, and other witnesses quite as hostile, to whom a moral dereliction could hardly be a mortal offence, were loud in praise of the purity of his walk in life."
• (poker) A situation where all players fold to the big blind, as their first action (instead of calling or raising), once they get their cards.
• (baseball) An award of first base to a batter following four balls being thrown by the pitcher; known in the rules as a "base on balls".
  "The pitcher now has two walks in this inning alone."

noun

• (biochemistry) A particular histidine kinase