IPA: //ʌnˈflæm.bɔɪ.ənt//
KK: /ʌnˈflæm.bɔɪ.ənt/
Not showy or flashy; simple and understated in style or appearance.
Her unflamboyant dress was perfect for the formal occasion.
Unflamboyant → It is formed from "un-" (meaning not) and "flamboyant" (from French *flamboyant*, meaning flaming or showy). The word "unflamboyant" means not showy or lacking in flamboyance.
Think of 'not' ('un-') being added to 'showy' ('flamboyant') — that's why unflamboyant means not showy.