11 letters

multicharge turbocharge undercharge ∙ supercharge ∙ hypercharge ∙ intercharge unsurcharge redischarge thaumaturge ∙ diabolifuge insectifuge ∙ electrofuge

12 letters

millerandage matrilineage patrilineage ∙ warehouseage overmortgage choleraphage myrmecophage phayllophage pollenophage neuronophage erythrophage galactophage ichthyophage phleborrhage lymphorrhage forecarriage ∙ postmarriage microleakage antibreakage overbreakage interlinkage preshrinkage subvassalage reassemblage ∙ waterbailage precartilage neocartilage intertillage ∙ intortillage barbouillage intervillage ∙ milligramage counterimage ∙ autodrainage overdrainage nonsiphonage companionage nonespionage bertillonage ∙ propatronage gazetteerage underaverage superaverage antisuffrage calculifrage preencourage disencourage misencourage rediscourage phonomassage vibromassage hydromassage superpassage intermessage orthovoltage undervoltage supervoltage disadvantage ∙ misadvantage midparentage Photomontage ∙ SuperMontage underfootage aecidiostage autofrettage apicurettage paralanguage ∙ metalanguage ∙ minilanguage gastrogavage gastrolavage preknowledge nonknowledge misknowledge ∙ straightedge ∙ Squarebridge Breckinridge countersiege proprivilege disprivilege ∙ intercollege Kriegsflagge varnpliktige megasporange zygosporange prechallenge mischallenge ∙ microsyringe enterchaunge ∙ reovercharge predischarge ∙ countergauge anophelifuge recentrifuge ∙

13 letters

contrabandage bacteriophage ∙ bactetiophage protozoophage anthropophage zoosaprophage harpactophage pigmentophage undercarriage ∙ frankmarriage aftermarriage intermarriage ∙ subassemblage mucocartilage Ursprungslage underdrainage ∙ backsiphonage pawnbrokerage milliamperage overencourage ∙ prediscourage thermomassage pneumomassage overweightage matriheritage protolanguage ∙ interlanguage reacknowledge Foreknowledge ∙ demisacrilege branchiostege reinterchange counterchange ∙ interexchange counterflange tetrasporange macrosporange microsporange countercharge ∙ overdischarge Siebengebirge Riesengebirge

14 letters

autocoprophage autohemorrhage Microshrinkage costicartilage fibrocartilage ∙ intercommonage stockbrokerage ∙ counterbarrage overdiscourage electromassage countermessage grandparentage preacknowledge disacknowledge ∙ misacknowledge superknowledge afterknowledge interknowledge Schwabenspiege Hochprozentige preinterchange trichosporange afterdischarge Fichtelgebirge

15 letters

macrophytophage necrophytophage nekrophytophage saprophytophage countermarriage pseudocartilage predisadvantage gastrostogavage gastrostolavage Tenyearlycharge ultracentrifuge ∙ supercentrifuge

16 letters

counterdisengage probacteriophage enterohemorrhage counterespionage counteradvantage nonforeknowledge Wehrmachtgefolge turbosupercharge

17 letters

autobacteriophage Violettfleischige

18 letters

Bindegewebsmassage

19 letters

corynebacteriophage pneumothermomassage Proportionatecharge

29 letters

Giftinconsiderationofmarriage

Words with a ∙ are valid Scrabble words (SOWPODS word list)