As used in this chapter—

(a) “Commission” means the United States Sentencing Commission;

(b) “Commissioner” means a member of the United States Sentencing Commission;

(c) “guidelines” means the guidelines promulgated by the Commission pursuant to section 994(a) of this title; and

(d) “rules and regulations” means rules and regulations promulgated by the Commission pursuant to section 995 of this title.