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thioketone

n. (context chemistry English) any analogue of an ketone, of general formula RC(=S)R', in which the oxygen has been replaced by sulfur

Wikipedia
Thioketone

Thioketones (also known as thiones or thiocarbonyls) are organosulfur compounds related to conventional ketones. Instead of the formula RC=O, thioketones have the formula RC=S, which is reflected by the prefix " thio-" in the name of the functional group. Unhindered alkylthioketones typically tend to form polymers or rings.