IPA: /ˌɪn.əˈdɛk.wə.si/
KK: /ɪnˈædɪkwəsi/
A situation where something is not enough or not good enough; a lack of quality or ability.
She felt a sense of inadequacy when comparing herself to her peers.
Inadequacy → It is formed from "in-" (meaning not) and "adequatus" (from Latin, meaning adequate or sufficient) and the suffix "-cy" (meaning the state or condition of). The word "inadequacy" refers to the state of being not sufficient or lacking in quality or quantity.
Think of 'not' ('in-') being combined with 'sufficient' ('adequatus') to remember that 'inadequacy' means a lack of sufficiency.