出典:Wiktionary
The noun is attested since 1914, from the colloquial verb smalm, smarm (“to smear, bedaub (hair, with pomade)”), attested since 1847, of unknown origin, perhaps somehow suggestive of the action. Verbal meaning "to smear with flattery" is from 1902.[1]
smarm (countable かつ uncountable, 複数形 smarms)
smarm (三人称単数 現在形 smarms, 現在分詞 smarming, 過去形および過去分詞形 smarmed)