arrière-train, arrière-trains, astreins, astreint, astreints, avant-train, avant-trains, aérotrains, boute-en-train, contrains, contraint, contraints, entrain, lutrin, lutrins, pétrin, pétrins, quatrain, quatrains, restreins, restreint, restreints, rétreint, train, train-train, trains, traintrain, étreins, étreint, étreints.