4 letters:
cope, dope, hope, koep, kope, lope, mope, nope, pope, rope, soap, sope, tope

5 letters:
chope, clope, crope, elope, g.o.p, groep, grope, gsoep, hagop, hopeh, knope, koepp, myope, n.o.p, prope, s.o.p, scope, shope, slope, snoep, stoep, stowp, swope, t.o.p, trope

6 letters:
-scope, -trope, agrope, arrope, ascope, aslope, canope, ethiop, galope, j-hope, koeppe, kscope, malope, merope, metope, scrope, strope, unrope

7 letters:
apocope, argiope, biotope, caliope, diacope, epitope, ethiope, freeotp, isotope, izotope, manrope, o-scope, outlope, schoepe, schoepf, schoepp, sterope, t-scope, towrope, upslope, v.s.o.p

8 letters:
agretope, allotope, amblyope, anoscope, antelope, antilope, bar soap, bellrope, bioscope, boltrope, diascope, docusoap, dragrope, envelope, epitrope, escalope, eythrope, fairhope, footrope, guy rope, headrope, hyperope, idiotope, inotrope, iriscope, myoscope, otoscope, paratope, pericope, polytope, reotrope, sandsoap, softsoap, top-rope, zoetrope

9 letters:
aeroscope, allotrope, altiscope, anti-pope, antitrope, auriscope, auroscope, azeotrope, baroscope, bath soap, bluescope, borescope, cantalope, cantaloup, cantelope, celoscope, coloscope, commscope, coniscope, conoscope, cryoscope, cymoscope, debuscope, docu-soap, downslope, echoscope, emmetrope, endoscope, engiscope, face soap, fetoscope, foldscope, gasoscope, gyroscope, haloscope, hemitrope, highscope, hodoscope, horoscope, interlope, isentrope, jackalope, jump-rope, jump rope, kinescope, koniscope, kymoscope, logiscope, manoscope, megascope, monoscope, monotrope, mutoscope, nasoscope, niloscope, nyctalope, osteocope, partenope, periscope, phalarope, pneoscope, polyscope, presbyope, protanope, pyroscope, rheoscope, rheotrope, ridgerope, rotascope, rotoscope, sematrope, skiascope, skip rope, soft-soap, soft soap, somascope, telescope, tightrope, toposcope, tritanope, veriscope, vitascope, zymoscope

10 letters:
amnioscope, anemoscope, angioscope, anisotrope, antroscope, astroscope, breastrope, cantaloupe, chronotope, clinoscope, colposcope, culdoscope, cycloscope, cystoscope, fiberscope, fibrescope, foetoscope, funduscope, glass-rope, gonioscope, green soap, haemoscope, hagioscope, haploscope, helioscope, heliotrope, hydroscope, hydrotrope, hygroscope, hypnoscope, iconoscope, interscope, lactoscope, laserscope, leucoscope, lithoscope, meatoscope, metroscope, microscope, myrioscope, necroscope, nephoscope, nightscope, orthoscope, otheoscope, ozonoscope, pantascope, parthenope, pelviscope, phacoscope, phakoscope, phonoscope, photoscope, platetrope, radarscope, radioscope, rectoscope, rhinoscope, ridge rope, riflescope, scotoscope, spiroscope, statoscope, tachyscope, teinoscope, vibroscope, videoscope, worldscope, zograscope

11 letters:
alethoscope, amblyoscope, arthroscope, cardioscope, chromascope, chromatrope, chromotrope, chronoscope, cinemascope, colonoscope, deuteranope, dichroscope, epidiascope, fluoroscope, futuroscope, gastroscope, glide slope, gonadotrope, graphiscope, graphoscope, invert soap, keratoscope, kinetoscope, laparoscope, liquid soap, lycanthrope, lychnoscope, marketscope, melanoscope, mirrorscope, misanthrope, nephroscope, odontoscope, opeidoscope, phantascope, pluvioscope, polariscope, polemoscope, proctoscope, pseudoscope, retinoscope, rope-a-dope, saddle soap, scleroscope, seismoscope, sideroscope, sniperscope, stauroscope, stereoscope, stethescope, stethoscope, stroboscope, synanthrope, techniscope, thaumatrope, thermoscope, toilet soap, towing rope, vectorscope, volumescope

12 letters:
aerobioscope, aethrioscope, anomaloscope, anorthoscope, bronchoscope, ceraunoscope, cyclonoscope, dichroiscope, ebullioscope, electroscope, enorthotrope, forlorn hope, galactoscope, galvanoscope, haematoscope, hypermetrope, hysteroscope, kaleidoscope, larungoscope, laryngoscope, leather soap, meteoroscope, oscilloscope, panendoscope, pay envelope, periodoscope, praxinoscope, radioisotope, resectoscope, rising slope, shaving soap, snooperscope, spectroscope, sphygmoscope, stomatoscope, synchroscope, telengiscope, the new pope, thoracoscope, urethroscope

13 letters:
biomicroscope, chromatoscope, diaphanoscope, dipleidoscope, esophagoscope, goat-antelope, goat antelope, opthalmoscope, parallelotope, pharyngoscope, phoneidoscope, phonendoscope, sigmoidoscope, skipping-rope, skipping rope, tachistoscope, therianthrope, trichinoscope, zoopraxiscope

14 letters:
anaglyphoscope, anamorphoscope, megalethoscope, oesophagoscope, ophthalmoscope, ophthalmotrope, phantasmascope, phosphoroscope, phototelescope, pithecanthrope, roentgenoscope, sable antelope, scintillascope, scintilloscope, spinthariscope, synchronoscope, the young pope

15 letters:
floral envelope, mediastinoscope, phenakistiscope, phenakistoscope, radio-telescope, radio telescope, solar telescope, stereomonoscope, telegraphoscope, telelectroscope, telepolariscope, telestereoscope, ultramicroscope, window envelope

16 letters:
light microscope, stanford-le-hope, telespectroscope

17 letters:
american antelope, cape of good hope, continental slope, garden heliotrope, microspectroscope, optical telescope, schmidt telescope, simple microscope, spectrohelioscope, winter heliotrope

18 letters:
galilean telescope, harnessed antelope, pronghorn antelope

19 letters:
compound microscope, electron microscope, gregorian telescope, newtonian telescope

20 letters:
reflecting telescope

22 letters:
astronomical telescope, hubble space telescope

26 letters:
james webb space telescope

4 letters:
lobe, robe

5 letters:
globe, probe

6 letters:
strobe, enrobe, aerobe

7 letters:
saprobe, disrobe, earlobe

9 letters:
katharobe

10 letters:
anglophobe, night-robe

11 letters:
space probe, francophobe

12 letters:
frontal lobe, hepatic lobe, judge's robe

13 letters:
parietal lobe, temporal lobe, academic robe, lounging robe

14 letters:
occipital lobe

15 letters:
celestial globe

19 letters:
ecclesiastical robe