tremissis

[ trih-mis-is ]
/ trɪˈmɪs ɪs /

noun, plural tre·mis·ses [trih-mis-eez] /trɪˈmɪs iz/.

Also called triens. a gold coin of the Eastern Roman Empire, the third part of a solidus, first issued in the 3rd century a.d.
a Merovingian gold coin imitating this.

Origin of tremissis

1700–10; < Late Latin trēmissis, equivalent to Latin trē(s) three + -missis as in sēmissis, Late Latin form of Latin sēmis semis (falsely analyzed as sē- + -missis)