Mammoth Uncensored Word List:
17 words ending with ta, 12 letters long

adenomyomata aerenchymata agrostemmata barotraumata chromonemata hemangiomata meningiomata mycoplasmata pachydermata parasyntheta parenchymata piroplasmata plasmosomata rejectamenta sarcolemmata staphylomata taramasalata