Learn how to say Thymuses correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word thymus:
noun (plural thymi /-mʌɪ/)
a lymphoid organ situated in the neck of vertebrates which produces T-lymphocytes for the immune system. The human thymus becomes much smaller at the approach of puberty.
late 16th century (denoting a growth or tumour resembling a bud): from Greek thumos ‘excrescence like a thyme bud, thymus gland’