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When used in this chapter -
(1) The term "industry affecting commerce" means any industry or activity in commerce or in which a labor dispute would burden or obstruct commerce or tend to burden or obstruct commerce or the free flow of commerce.
(2) The term "strike" includes any strike or other concerted stoppage of work by employees (including a stoppage by reason of the expiration of a collective-bargaining agreement) and any concerted slowdown or other concerted interruption of operations by employees.
(3) The terms "commerce", "labor disputes", "employer", "employee", "labor organization", "representative", "person", and "supervisor" shall have the same meaning as when used in subchapter II of this chapter.
(June 23, 1947, ch. 120, title V, §501, 61 Stat. 161.)