From Wiktionary, the free dictionary
From rikka (“mote”) + rokassa (“in the soup”), probably chosen for phonetic similarity.
- IPA(key): /ˈrikːɑ ˈrokɑsːɑ/, [ˈrikːɑ̝ ˈro̞kɑ̝s̠ːɑ̝]
rikka rokassa
- (idiomatic) an insignificant detail, just one thing among many
See rikka.