IPA: /ˈhæpənˌtʃæns/
KK: /ˈhæpənˌtʃæns/
An occurrence or event that happens by chance; a coincidence.
It was pure happenchance that we met at the café.
Happenchance is formed from "happen" (from Middle English *happen*, meaning to occur or take place) and "chance" (from Old French *chance*, meaning fortune or luck). The word refers to events that occur by chance or luck.
Think of events that 'occur' ('happen') by 'luck' ('chance') — that's what happenchance means.