IPA: //ˌʌn.kənˌdʒiː.niˈæl.ɪ.ti//
KK: /ʌnˌkɒnˈdʒiːniəlɪti/
A quality or state of being unfriendly or not pleasant to others.
The uncongeniality of the atmosphere made it difficult for the guests to enjoy the party.
Uncongeniality → It is formed from "un-" (meaning not), "congenial" (from Latin "congenialis", meaning suitable or agreeable), and "-ity" (meaning the state or quality of). The word "uncongeniality" refers to the state of being not suitable or agreeable, often in terms of personality or environment.
Think of 'not' ('un-') being combined with 'suitable or agreeable' ('congenial') to remember that 'uncongeniality' means a lack of suitability or agreeableness.