concentrator

abdicator, abnegator, activator, actuator, adulator, advocator, agitator, alligator, allocator, animator, annotator, applicator, arbitrator, aspirator, aviator, brachiator, buccinator, calculator, calibrator, captivator, carburetor, castigator, circulator, commentator, commutator, compensator, compurgator, confiscator, congregator, consecrator, consummator, contemplator, corporator, correlator, cultivator, decorator, defalcator, delegator, demonstrator, denigrator, depredator, desecrater, designator, detonator, deviator, dissipater, dominator, dura mater, educator, elevator, emulator, escalator, estimator, excavator, explicator, expurgator, extirpator, fabricator, fascinator, figure skater, flocculator, formulator, fornicator, fractionator, fumigator, generator, gladiator, hesitater, hibernator, imitator, immolator, impregnator, incubator, indicator, infiltrator, in-line skater, innovator, inhalator, inspirator, instigator, insulator, integrator, lacrimator, liberator, liquidator, literator, lubricator, macerator, masticator, mediator, mitigator, moderator, modulator, motivator, mutilator, navigator, nomenclator, nominator, numerator, obturator, operator, orchestrator, oscillator, peculator, percolator, perforator, perpetrator, pia mater, pollinator, postulator, procreator, procurator, promulgator, propagator, punctuator, radiator, re-creator, remonstrator, renovator, resonator, respirator, revelator, roller skater, rubricator, rusticator, salivator, second-rater, selling-plater, separator, simulator, stimulator, subjugator, Sunset Crater, syncopator, syndicator, tabulator, terminator, vaccinator, vacillator, valuator, venerator, ventilator, vindicator, violator, vitiator