fly by night operation

business, occupation, employment; pursuit; what one is doing, what one is about; affair, concern, matter, case., matter in hand, irons in the fire; thing to do, agendum, task, work, job, chore [U.S.], errand, commission, mission, charge, care; duty., part, role, cue; province, function, lookout, department, capacity, sphere, orb, field, line; walk of life; beat, round, routine; race, career., office, place, post, chargeship, incumbency, living; situation, berth, employ; service (servitude); engagement; undertaking., vocation, calling, profession, cloth, faculty; industry, art; industrial arts; craft, mystery, handicraft; trade (commerce)., exercise; work (action); avocation; press of business (activity).

pass one's time in, employ one's time in, spend one's time in; employ oneself in, employ oneself upon; occupy oneself with, concern oneself with; make it one's business; undertake; enter a profession; betake oneself to, turn one's hand to; have to do with (do)., drive a trade; carry on a trade, do a trade, transact a trade, carry on business, do business, transact business; keep a shop; ply one's task, ply one's trade; labor in one's vocation; pursue the even tenor of one's way; attend to business, attend to one's work., officiate, serve, act; act one's part, play one's part; do duty; serve the office, discharge the office, perform the office, perform the duties, perform the functions of; hold an office, fill an office, fill a place, fill a situation; hold a portfolio., be about, be doing, be engaged in, be employed in, be occupied with, be at work on; have one's hands in, have in hand; have on one's hands, have on one's shoulders; bear the burden; have one's hands full (activity) [more]., be in the hands of, be on the stocks, be on the anvil; pass through one's hands.

businesslike; workaday; professional; official, functional; busy (actively employed); on hand, in hand, in one's hands; afoot; on foot, on the anvil; going on; acting.

in the course of business, all in one's day's work; professionally,