3 letters:
hof, mof, off

4 letters:
asaf, boff, coif, doff, goff, haaf, hauf, hoff, koff, lauf, poff, roff

5 letters:
afsof, bbiaf, bogof, cebaf, cloff, coffe, cough, croff, dodaf, feoff, goffe, gough, gprof, graaf, groff, hauff, joffe, knauf, knoff, knopf, ma fh, musaf, najaf, nasaf, nataf, ncaaf, nroff, oglaf, pilaf, prof., pskov, quaff, quoif, raphe, rocof, roffe, sadaf, scoff, setaf, shoff, skoff, snoff, staaf, stoff, taufe, tawaf, titov, troff, usaaf, waffe, yakov

6 letters:
aikoff, ashraf, asoiaf, averof, baraff, bedaff, beloff, centaf, cutoff, dosaaf, duboff, geldof, go off, herauf, imhoff, in-off, inhofe, karkov, kloffe, knauff, lagnaf, layoff, lihaaf, linhof, madoff, mansaf, markov, masyaf, mcgoff, neogaf, on-off, payoff, popoff, putoff, rakoff, ripoff, ruboff, rudolf, runoff, rykoff, sadoff, schaaf, schoff, shroff, stauff, taaffe, teeoff, tipoff, trough, uphoff, wiglaf, yaakov

7 letters:
backoff, beg off, buy off, cap off, castoff, cut-off, cut off, day off, die-off, die off, dolloff, dropoff, eckhoff, evanoff, faceoff, falloff, far-off, fob off, fuckoff, get off, handoff, infeoff, jackoff, jumpoff, kickoff, lay-off, lay off, leadoff, lenhoff, let-off, let off, liftoff, lip off, log-off, log off, lop off, lubinov, luzhkov, markoff, mid-off, minkoff, molotov, mus'haf, nabokov, neuhoff, nip off, nod off, nordoff, olthoff, one-off, pan off, pay-off, pay off, pickoff, playoff, pop off, pss sof, put-off, puthoff, put off, rip-off, rip off, rockoff, rolloff, romanov, rub-off, rub off, run-off, run off, rybakov, saratov, satloff, schroff, selloff, set-off, set off, shicoff, shutoff, spinoff, takeoff, tap-off, tarnoff, tee off, tip-off, tip off, top off, turnoff, walkoff, wemhoff, zuganov

8 letters:
back off, bake-off, bear off, bind off, bite off, blastoff, blow-off, blow off, bohnhoff, boil-off, brushoff, bulgakov, bump off, burn off, buzz off, call off, cart off, cast-off, cast off, cerenkov, checkoff, chip off, chop off, come off, cook-off, cool off, dash off, dope off, doze off, draw off, drop-off, drop off, dust-off, ease off, eickhoff, even off, face-off, face off, fall-off, fall off, federoff, fend off, flow off, fruehauf, give off, goof-off, hand-off, hard-off, haul off, head off, hold off, jack off, jerk-off, jerk off, jump-off, jump off, keep off, kick-off, kick off, kill off, kiss-off, knockoff, kohlhoff, kolokoff, laid-off, lead-off, lead off, left-off, lift-off, lift off, live off, mark off, mazeltov, melt off, metacafe, pair off, palm off, pass off, patricof, peel off, pick-off, pick off, play-off, potthoff, poznikov, pull-off, pull off, rake-off, rake off, reel off, ribicoff, ride off, roar off, roll-off, roll off, romanoff, rope off, rush off, saathoff, sawn-off, seal off, selikoff, sell-off, sell off, send-off, send off, shernoff, shoo off, show-off, show off, shut-off, shut off, sign-off, sign off, skim off, slip off, snap off, snip off, spin-off, spin off, standoff, step-off, stop-off, tail-off, take-off, take off, tear-off, tear off, tell off, theosoph, tick off, time off, toss off, tradeoff, turn-off, turn off, walk-off, walk off, ward off, wash-off, wave-off, wave off, wear off, well-off, westhoff, wind off, wipe off

9 letters:
bauernhof, blast-off, blast off, block off, bound off, break-off, break off, bring off, brockhoff, brush-off, brush off, bully-off, bully off, cargonoff, carry off, chebrikov, check off, cherenkov, choke off, clear off, click off, clock off, close off, count off, cream off, cross off, dance-off, drift off, drive-off, drive off, fight off, first off, flake off, fling off, foist off, friedhoff, gorbachev, gorchakov, hands-off, holzstoff, knock-off, knock off, krushchev, laugh off, leave off, lermontov, level off, loose off, luftwaffe, maslyukov, mouth off, musharraf, osterhoff, pentrough, rinse off, round-off, round off, sawed-off, scare off, schoenhof, shade off, shake off, shove off, slack off, sleep off, sneak off, sound off, spark off, spiel off, split-off, stand-off, start-off, stave off, steinhoff, swear off, sweat off, sweep off, taper off, tartikoff, tegethoff, throw-off, throw off, touch off, trade-off, whisk off, write-off, write off

10 letters:
better-off, bugger off, charge-off, christophe, coco gauff, cordon off, finish off, firing off, freeze off, kafelnikov, khlebnikov, khrushchev, kunststoff, lopped off, metchnikov, mobssl-uaf, on and off, pissed-off, polish off, raffle off, rattle off, sauerstoff, screen off, shepseskaf, siphon off, spirit off, sponge off, square off, strike off, stroganoff, switch off, taking-off, ticked-off, vanderhoff, westerhoff

11 letters:
alan schaaf, auction off, baryshnikov, benninghoff, brinkerhoff, cecilienhof, closing off, cooling-off, curtain off, cutting off, damping-off, damping off, drawing off, eavestrough, falling-off, falling off, goofing off, have it off, heterotroph, hoelterhoff, jacking off, jerking off, kalashnikov, leading off, metchnikoff, panzerwaffe, partner off, pension off, raskolnikov, sending-off, slacken off, telling-off, ticking-off, trigger off, wasserstoff, wunderwaffe

12 letters:
breaking off, brinckerhoff, frighten off, separate off, tapering off, tiger shroff, vanderschaaf

13 letters:
partition off, take time off

14 letters:
katee sackhoff, rinat akhmetov, sloping trough, whooping cough

15 letters:
beef stroganoff, jean-christophe, kneading-trough, partitioned off

16 letters:
chemoheterotroph, photoheterotroph, roll-on/roll-off, volksgerichtshof

18 letters:
escape from tarkov, kliment kolesnikov

21 letters:
nahverteidigungswaffe, shoot one's mouth off

24 letters:
ferris bueller's day off

26 letters:
the great british bake off