Britain's rhymes with:
britains, britons, britons', britains, britons, britons', britains, britons, britons', gittens, kittens, litton's, mittens
Britain's sounds like:
baritones, bartmess, bartnick, bartnicki, bartnik, barton's, bartunek, berating, birthing, boarding, boardinghouse, boardinghouses, boardings, borden's, bortnick, brademas, braiding, breading, breathing, breeden's, breeding, britains, britannica, britons, britons', broadening, broadens, broadnax, brodnax, brooding, bruting, burdening, burdens, burdine's, burdines, burtness, burton's