What does Tigris mean in Hebrew?

Answer 1

The only Hebrew word for Tigris is חדקל pronounced khee-DECK-el. But חדקל has no meaning in Hebrew because it was borrowed from Akkadian.

The word Tigris is a Greek form of the same word borrowed from Akkadian.

The original Sumerian Idigna or Idigina was probably the word for "running water", which can be interpreted as "the swift river", contrasted to its neighbour, the Euphrates, whose leisurely pace caused it to deposit more silt and build up a higher bed than the Tigris.

The Sumerian form was borrowed into Akkadian as Idiqlat, and from there into the other Semitic languages.