Unseemly means not proper for the occasion. Unseemly haste, an unseemly row, unseemly behaviour.
It judges by the setting rather than by morality — unseemly haste at a funeral is not wrong so much as wrong there, which is what makes the word so useful in polite criticism. It is formal and slightly old-fashioned. Note seemly, which survives mainly as its opposite; and that seem here means to be fitting.
1adjectiveunseemlyNot proper for the occasion.
“Everyone agreed that laughing loudly at the funeral had been unseemly.”
synonyms: improper, indecorous
unseemly is a quality of impropriety.
Un- plus seemly, from Old Norse soemiligr, fitting. Seem, in the sense of being fitting, is the root.
Middle English
unsemli
English, today
unseemly
From Middle English unsemli, probably a úsǽmiligr; equivalent to un- + seemly. Cognate with Icelandic ósæmileg (“offensive”), Norwegian usømmelig (“unseemly”), Danish usømmelig (“unseemly”), German unziemlich.
Etymology from Wiktionary, CC BY-SA