Italian word sinceramente comes from Italian -mente, Italian sincero ((obsolete) sound, genuine. Sincere, honest.)

Detailed word origin of sinceramente

Dictionary entry	Language	Definition
-mente	Italian (ita)	(productive) Used to form adverbs from adjectives; -wise, -ly, -ally.
sincero	Italian (ita)	(obsolete) sound, genuine. Sincere, honest.
sinceramente	Italian (ita)	Sincerely, honestly.

Words with the same origin as sinceramente