3 letters:
ude

4 letters:
cude, cued, dude, feud, food, gude, hued, jude, lewd, mood, nude, rood, rude, ruud, sood, sued, tude

5 letters:
-tude, abood, aboud, blude, blued, boodh, booed, box2d, brood, chude, clued, cooed, coude, crude, dewed, drood, drude, elude, etude, ew dd, exude, glued, hewed, ifood, itu-d, jehud, jewed, koode, likud, looed, masud, mewed, mooed, nkg2d, noeud, oohed, plude, pooed, prude, pseud, rhude, roode, salud, shoed, shude, slued, snood, spued, stude, tewed, trude, trued, who'd, wooed, yehud, you'd

6 letters:
abboud, ablude, allude, almude, brewed, canoed, chewed, clewed, crewed, delude, denude, dulude, elioud, endued, ensrud, ensued, flewed, hudood, illude, imbued, indued, live2d, mahmud, masood, masoud, mtu dd, palude, poohed, pseud-, queued, s1000d, shewed, shooed, shrewd, skewed, slewed, spewed, stewed, strood, strude, tabued, thewed, viewed, zarude

7 letters:
accrued, actitud, alamoud, aptitud, bedewed, catfood, cocos2d, collude, d'etude, dark0de, debuted, dixmude, dogfood, embrued, eshewed, extrude, imbrued, include, intrude, latitud, mahmood, mahmoud, maksoud, massoud, miscued, nonfood, obtrude, occlude, petfood, prelude, pursued, reclude, renewed, rotrude, screwed, seafood, seclude, sinewed, solar2d, statued, strewed, subdued, tabooed, true hd, unglued, unitude, unshoed, vinewed

8 letters:
abstrude, acritude, altitude, amplitud, aptitude, attitude, boohooed, buy food, cat food, ccsd ued, conclude, cuckooed, devalued, direct2d, disclude, dog food, egritude, eschewed, fastfood, finitude, gratitud, gumshoed, habitude, hallooed, hebetude, hey jude, holyrood, hoodooed, indofood, iznogoud, junkfood, latetude, latitude, lenitude, megafood, mildewed, mm..food, multitud, non-food, orbitude, pencil2d, pet-food, pet food, postlude, preclude, protrude, quaalude, quietude, raditude, retinued, reviewed, seminude, solitude, subtrude, syncrude, tabitude, tattooed, ulan-ude, unbrewed, unchewed, uncrewed, unissued, vinnewed, voodooed

9 letters:
amaritude, amplitude, anxietude, aquiclude, assuetude, barbecued, barbequed, beatitude, beshrewed, bestrewed, bird food, buxtehude, cattitude, celsitude, certitude, claritude, construed, desuetude, disillude, dudesnude, dulcitude, fact mood, fast-food, firmitude, fortitude, gratitude, hackitude, hastilude, insinewed, insuetude, interlude, latittude, lattitude, lentitude, limpitude, lindamood, lippitude, longitude, magnitude, mollitude, multitude, negritude, nigritude, oversewed, parvitude, platitude, plenitude, previewed, rectitude, segnitude, servitude, shampooed, snowshoed, solicitud, superfood, torpitude, tumblewed, turpitude, unpursued, unrenewed, unscrewed, unsubdued, vastitude, wedgitude, wholefood

10 letters:
acerbitude, al-namrood, ballyhooed, blood feud, colatitude, consuetude, crebritude, definitude, exacritude, exactitude, fresh food, hellbrewed, homebrewed, horseshoed, inaptitude, ineptitude, inertitude, infinitude, inquietude, interclude, mansuetude, overviewed, pinguitude, plentitude, sanctitude, serenitude, similitude, snack food, solicitude, spoon food, superglued, unquietude, unrevenued, vajiravudh

11 letters:
canned food, casper ruud, common mood, corkscrewed, countersued, decrepitude, disertitude, disquietude, egg as food, finger food, frankenfood, frozen food, google feud, health food, home-brewed, incertitude, ingratitude, interviewed, midlatitude, pooh-poohed, promptitude, pulchritude, rabbit food, senectitude, thithikudhe

12 letters:
correctitude, devil's food, disquiettude, indefinitude, inexactitude, low-altitude, misconstrued, multi-valued, takeout food, yongchaiyudh

13 letters:
consimilitude, dell latitude, dissimilitude, high-altitude, honda prelude, overmultitude, peer-reviewed

14 letters:
breakfast food, horse latitude, lunar latitude, verisimilitude

15 letters:
dehydrated food, imperative mood, indicative mood, mental attitude, miraculous food, pious platitude

16 letters:
change magnitude, convenience food, inverisimilitude, line of latitude

17 letters:
delicatessen food, inherent aptitude, line of longitude

18 letters:
ahmad shah massoud, celestial latitude, defensive attitude, order of magnitude

19 letters:
celestial longitude, change of magnitude

20 letters:
parallel of latitude

29 letters:
one hundred years of solitude

34 letters:
freedom from involuntary servitude