IPA: //ʌnˈsiːmli.nəs//
KK: /ʌnˈsimliːnəs/
The condition of being inappropriate or improper in behavior or appearance.
His unseemliness at the formal event made everyone uncomfortable.
Unseemliness → It is formed from "un-" (meaning not) and "seemly" (from Old English "seemlic", meaning proper or fitting) and the suffix "-ness" (meaning the state of being). The word "unseemliness" refers to the state of not being proper or fitting.
Think of 'not' ('un-') being combined with 'proper' ('seemly') to remember that 'unseemliness' means the state of being improper.