Parashas Bamidbar · Passuk 4:13
They shall remove the ashes from the [copper] altar and spread a purple cloth over it.
Chabad.org — English translation + Rashi
Source: Chullin 137b.
English: “And they shall remove the ashes (dishnu)” — it was taught: R’ Yehudah says: What is “dishnu”? Clearing / removing the ash.
In context: The verb is midrashically fixed in the sense of clearing the ash rather than a different root meaning.
Custom
Chazal clarify that “dishnu” means the clearing of the ashes from the altar.