IPA: /ˌɪnəˈpɔːrtʃuːnli/
KK: /ɪnˈɑːpərtʃuːnli/
In a way that is not suitable or convenient for a particular situation.
He arrived inopportunely during the meeting, causing a distraction.
Inopportunely → It is formed from "in-" (meaning not) and "opportunus" (from Latin, meaning suitable or favorable) and the suffix "-ly" (meaning in a manner). The word "inopportunely" means in a manner that is not suitable or favorable, often referring to something happening at an inconvenient time.
Think of 'not' ('in-') being combined with 'suitable' ('opportunus') to remember that 'inopportunely' describes something that happens at an unsuitable or inconvenient time.