5 letters:
beter, detre, eater, fetor, jeter, liter, litre, meter, metre, peter, teter, zetor

6 letters:
-meter, -metre, aliter, beater, cretor, deater, deeter, dieter, feater, foetor, geeter, heater, jeeter, keator, keeter, keiter, keytar, meeter, mitter, neater, peeter, pieter, preter, pretor, rieter, saeter, seater, sliter, spitir, teater, teeter, ureter, vietor, yeater

7 letters:
-seater, ammeter, arreter, bleater, cheater, demeter, demetre, e-meter, eat her, fleeter, freeter, greeter, molitor, oometer, pleater, praeter, praetor, preter-, sheeter, skeeter, sleeter, sweeter, treater, tweeter

8 letters:
anteater, avometer, beat her, defeater, depleter, diametre, elfmeter, exalitre, exametre, figeater, luxmeter, maneater, meet her, ohmmeter, oximeter, physeter, praeter-, reheater, repeater, streater, streator, streeter, strieter, st peter, vanmeter, vanmetre

9 letters:
aerometer, ant-eater, antimeter, attolitre, attometre, bee-eater, beefeater, bee eater, bolometer, champetre, competere, completar, completer, crabeater, croweater, cryometer, dasymeter, decametre, deciliter, decilitre, decimeter, decimetre, dekametre, dosemeter, eggbeater, entreater, ergometer, expositor, fisheater, fluxmeter, focimeter, gasometer, gas meter, gigalitre, gigameter, gigametre, gnateater, greet her, halometer, hazemeter, holometer, kilolitre, kilometer, kilometre, konimeter, labimeter, lanameter, logometer, man-eater, manometer, meateater, megameter, megametre, mekometer, mililiter, milometer, nanolitre, nanometer, nanometre, nilometer, oenometer, overeater, petalitre, petameter, petametre, picolitre, picometre, preheater, propretor, pyoureter, rainmeter, receiptor, retreater, salimeter, salometer, saltpetre, schleeter, seedeater, similiter, sin-eater, sonometer, tasimeter, taximeter, telemeter, teralitre, terameter, terametre, toadeater, tonometer, treat her, ureameter, vinometer, wattmeter

10 letters:
acetimeter, acidimeter, all-seater, barkometer, bathymeter, bhangmeter, blue peter, browbeater, calcimeter, campimeter, centiliter, centilitre, centimeter, centimetre, clinometer, coal-meter, coulometer, cyanometer, cyclometer, decremeter, densimeter, discreeter, drumbeater, egg-beater, fathometer, femtometre, fire-eater, gas heater, geodimeter, goldbeater, gravimeter, hectolitre, hectometre, honeyeater, hypermeter, joulemeter, klinometer, leadbeater, macrometer, maltreater, mentimeter, micrometre, milliliter, millilitre, millimeter, millimetre, multimeter, myrialitre, myriameter, myriametre, neotheater, oil heater, opacimeter, pachymeter, pantometer, passometer, pelvimeter, planimeter, planometer, platymeter, pleximeter, propraetor, pulsimeter, pulsometer, qualimeter, rug beater, sillometer, snow eater, stadimeter, stenometer, sulfameter, tachymeter, tensimeter, tenthmetre, tetrameter, toad-eater, turgometer, two-seater, vacuometer, voltameter, yoctolitre, yoctometre, yottalitre, yottameter, yottametre, zentimeter, zeptolitre, zeptometre, zettalitre, zettameter, zettametre

11 letters:
actinometer, alcalimeter, algesimeter, amperemeter, auxanometer, brontometer, chlorometer, co-oximeter, coercimeter, cubic meter, elastometer, fluorimeter, gold-beater, honey-eater, honey eater, indigometer, intoximeter, light meter, lotos-eater, lotus-eater, lotus eater, nonsecretor, opium-eater, plessimeter, pluviameter, pyranometer, saint peter, stereometer, superheater, torquemeter, velocimeter, water meter, wife-beater, windcheater, worldbeater

12 letters:
cephalometer, common meter, complete her, ductilimeter, extensimeter, galvanometer, globulimeter, hannah jeter, microammeter, milliammeter, newton-meter, newton-metre, penetrameter, profilometer, solar heater, space heater, square meter, turbidimeter, viscosimeter, water heater, world-beater

13 letters:
albuminimeter, alcoholometer, anthropometer, carpet beater, gravity meter, kilogrammetre, phall-o-meter, pneumonometer, postage meter, submillimeter

14 letters:
baromacrometer, dynactinometer, exposure meter, giant anteater, great anteater, haematinometer, haemomanometer, kilogram-meter, microbolometer, photogrammeter, scintillometer, silky anteater, spiny anteater

15 letters:
banded anteater, carmelita jeter, electric heater, gram-centimeter, kerosene heater, lactodensimeter, lesser anteater, micromillimeter, micromillimetre, transmissometer

16 letters:
cubic centimeter, cubic millimeter, sphygmomanometer, thermogravimeter, trick-or-treater

18 letters:
new world anteater, psychogalvanometer, spectrofluorimeter

4 letters:
igor

5 letters:
cedar, eager, t-bar, eagre, regur, uigur, vidor

6 letters:
seeder, detour, beeper, meager, meagre, reaper, keeper, beaker, feeder, peeper, seeker, weeper, leader, reader, deeper, fieger, veadar, weaker

7 letters:
bleeder, chequer, breeder, creeper, sleeper, speeder, sneaker, speaker, sweeper, cheaper, uneager

8 letters:
squeaker, streaker, besieger, wheatear, strieker, toreador

9 letters:
beleaguer, red cedar

10 letters:
lip reader, lay reader, true cedar, zoo keeper

11 letters:
grim reaper, loss leader, white cedar, atlas cedar, mind reader, big leaguer, canoe cedar, japan cedar, placeseeker, self-feeder, self-seeker, woodcreeper

12 letters:
floor leader, alaska cedar, civic leader, civil leader, diary keeper, ground cedar, honeycreeper, labor leader, mouthbreeder, oregon cedar, pencil cedar, snake feeder, yellow cedar

13 letters:
incense cedar, spanish cedar, bermuda cedar, chilean cedar, major leaguer, market keeper, minor leaguer, saloon keeper, stock breeder, strike leader

14 letters:
carpet sweeper, japanese cedar, brothel keeper, chimneysweeper, lawson's cedar, little leaguer, public speaker, station keeper, stinking cedar, street sweeper

15 letters:
majority leader, minority leader, business leader, himalayan cedar, military leader, national leader, pleasure seeker

16 letters:
intercom speaker, philippine cedar, political leader, religious leader, spiritual leader

17 letters:
eastern red cedar, western red cedar, port orford cedar, coast white cedar, lighthouse keeper

18 letters:
east african cedar, southern red cedar

19 letters:
civil rights leader, valedictory speaker

20 letters:
atlantic white cedar, northern white cedar, southern white cedar