propre comme un sou neuf

== French == === Etymology === Literally, “clean as a brand new penny”. === Pronunciation === IPA(key): /pʁɔ.pʁə kɔ.m‿œ̃ su nœf/ === Adjective === propre comme un sou neuf (plural propres comme des sous neufs) (simile) Very clean; squeaky clean; clean as a whistle ==== Usage notes ==== Only used in the physical sense of clean, never the moral one, which is carried by blanc comme neige.