use '?' for JOKER (blank)

From letters G, A, S, T, R, O, E, N, T, E, R, I, T, I, S  I made following words

15 letter words

gastroenteritis[16]

13 letter words

registrations[14]

12 letter words

interrogates[13], registration[13], reiterations[12], stationeries[12]

11 letter words

garnierites[12], signatories[12], reasserting[12], reassorting[12], reiterating[12], interrogate[12], integrators[12], instigators[12], registrants[12], reassertion[11], reiteration[11], antistories[11], tristearins[11], interstates[11]

10 letter words

orangeries[11], seignories[11], organisers[11], regression[11], garnierite[11], originates[11], generators[11], roistering[11], stingarees[11], registries[11], estrangers[11], retreating[11], integrator[11], negotiates[11], argentites[11], estreating[11], integrates[11], interstage[11], teratogens[11], instigator[11], registrant[11], restarting[11], instigates[11], gestations[11], strategies[11], grittiness[11], resittings[11], stringiest[11], strategist[11], seriations[10], serotinies[10], rotisserie[10], serrations[10], itinerates[10], orientates[10], iterations[10], tertiaries[10], tristearin[10], reinstates[10], tanistries[10], restations[10], stationers[10], striations[10], artistries[10], restraints[10], traitoress[10], transistor[10], interstate[10], attritions[10], titrations[10], enstatites[10], intestates[10], satinettes[10]

9 letter words

orangerie[10], regainers[10], reraising[10], organiser[10], erigerons[10], isogenies[10], organises[10], egression[10], seigniors[10], signories[10], resigners[10], engrosser[10], garrisons[10], originate[10], retearing[10], generator[10], agentries[10], gratinees[10], reseating[10], stingaree[10], grainiest[10], seriating[10], reignites[10], orangiest[10], stereoing[10], rigatonis[10], sortieing[10], irrigates[10], estranger[10], arresting[10], serrating[10], stringier[10], resorting[10], restoring[10], gaseities[10], agonistes[10], egestions[10], greasiest[10], estranges[10], greatness[10], sergeants[10], asserting[10], astringes[10], ganisters[10], resisting[10], sistering[10], estragons[10], estrogens[10], assorting[10], organists[10], registers[10], strangers[10], restrings[10], stringers[10], stirrings[10], rigorists[10], negotiate[10], argentite[10], integrate[10], iterating[10], teratogen[10], retorting[10], instigate[10], gestation[10], aigrettes[10], restating[10], retasting[10], resetting[10], retesting[10], striating[10], resitting[10], tetragons[10], retargets[10], garotters[10], garrottes[10], stingiest[10], reasoners[9], seriation[9], retainers[9], ternaries[9], serration[9], orienters[9], orneriest[9], reorients[9], interiors[9], arsenites[9], irateness[9], resinates[9], stearines[9], teariness[9], ostiaries[9], earstones[9], resonates[9], assertion[9], senoritas[9], serotines[9], restrains[9], strainers[9], tarriness[9], inserters[9], reinserts[9], itinerate[9], orientate[9], iteration[9], reinstate[9], enteritis[9], interties[9], retinites[9], restation[9], stationer[9], tenorites[9], striation[9], arteritis[9], irritates[9], ratteners[9], restraint[9], retirants[9], irritants[9], nitrators[9], satieties[9], anisettes[9], tetanises[9], tensities[9], noisettes[9], teosintes[9], sestertia[9], treatises[9]