falla eins og flís við rass

Literally ‘to fit as tightly as a chip (metaphorically a thin, close cut) against the ass’. This idiom is relatively recent in the Icelandic language with the oldest example in the Orðabók Háskólans's (“the University Dictionary”) ritmálssafn (“corpus of written language”) dating from the early 19th century from Guðmundur Jónsson's málsháttaasafn (“corpus of idioms”).

falla eins og flís við rass (strong verb, third-person singular past indicative féll eins og flís við rass, third-person plural past indicative féllu eins og flís við rass, supine fallið eins og flís við rass)

1. (idiomatic, simile, intransitive) to fit like a glove, to fit perfectly

   Þetta fellur eins og flís við rass.

   This fits like a glove.

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