IPA: /ˌʌndəˈrʌnɪŋ/
KK: /ʌndərˈrʌnɪŋ/
A fishing technique that allows for the simultaneous removal of fish from hooks and the re-baiting of those hooks.
The fishermen used underrunning to efficiently catch and prepare their gear.
Underrunning is formed from "under-" (meaning beneath or below) and "running" (from Old English "rinnan", meaning to flow or move). The word describes the action of running beneath something, often used in contexts like water flowing under a bridge or a process occurring at a lower level.
Think of something moving 'beneath' ('under-') while 'flowing' or 'moving' ('rinnan') — that's what underrunning means.