tristimonium
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tristimonio Noun: neuter dative singular, Noun: neuter ablative singular of tristimonium
trīstimōnium, iī, n. (tristis), die Traurigkeit, Petron. 63, 4.
trīstĭmōnĭum, (16) ĭī, n. , tristesse : Petr. 63, 4.
ægrimonium, in Fragmento Petronii de Cœna Trimalcionis pag. 51.