Trettin rhymes with:
retin, benten, bettin, retin, sweatin', abrutyn, agustin, anniston, augustyn, austen, bastin, battin, begotten, bendectin, benten, bertin, bettin, bolotin, boorstin, botin, braton, brattin, brittin, buntin, buntyn, bustin, catain, celestin, chattin, clandestine, claritin, constantin, cortin, costin, curtin, cyhexatin, dantin, demartin, destin, dreighton, dustin, eastin, entin, erythropoietin, fightin', finkielstain, fortin, gallatin, gartin, gilmartin, guilmartin, gustin, hartin, highfalutin, intermountain, kilmartin, kirstin, krigsten, kristin, lattin, leptin, liftin, loftin, longtin, lovastatin, loyalton, macrodantin, martyn, mastin, micatin, mostyn, mustin, nejamatin, partin, patin, pattin, progestin, quentin, quintin, rasputin, recoton, remmington, retin, rohatyn, rustin, sanmartin, santin, sartin, scrotten, seetin, shootin', statin, stattin, st_martin, sweatin', therafectin, tramontin, tustin, waitin', warkentin, westin
Trettin sounds like:
tarrytown, tartan, teradyne, tetterton, thirteen, thorton, threaten, tradition, trautman, trautmann, trautwein, tretinoin, tritium, triton, trodden, trotman, trotten, troutman, troutwine, turton