WordNet sense 1 (a short theatrical performance that is part of a longer program):

act, bit, number, turn, number

WordNet sense 2 (a set sequence of steps, part of larger computer program):

function, procedure, subroutine, subprogram

WordNet sense 3 (in accordance with fixed order or procedure or principle):

regular

WordNet sense 4 (found in the ordinary course of events):

everyday, mundane, quotidian, unremarkable, workaday

WordNet sense 5 (not exceptional in any way especially in quality or ability or size or degree):

ordinary

WordNet sense 6 (an unvarying or habitual method or procedure):

modus operandi