expert vs efficiency engineer

Other hyponyms of expert include ace, adept, champion, genius, hotshot, maven, mavin, sensation, star, superstar, virtuoso, whiz, whizz, wiz, wizard, agronomist, all-rounder, all arounder, analyst, analyst, anatomist, antiquarian, antiquary, archaist, arbiter, supreme authority, archer, bowman, authority, black belt, cabalist, kabbalist, calculator, computer, estimator, figurer, reckoner, climatologist, computer expert, computer guru, cosmetologist, efficiency expert, exegete, genealogist, geographer, horticulturist, plantsman, investigator, jurist, legal expert, lapidarist, lapidary, logician, logistician, mnemonist, mythologist, nerd, commentator, observer, out-and-outer, parliamentarian, past master, prosthetist, pteridologist, guide, pathfinder, scout, shark, shooter, shot, specialiser, specialist, specializer, talent, technician, technocrat, healer, therapist, old-timer, old hand, old stager, oldtimer, stager, veteran, warhorse.