What is the meaning of Arrowroot?

Maranta arundinacea from the Marantaceae family, a large perennial herb native to the Caribbean area with green leaves about 15 centimeters long.

Usually preceded by an attributive word: some other plant whose rhizomes are used to prepare a substance similar to arrowroot (sense 3), such as Zamia integrifolia (Florida arrowroot) or Pueraria montana var. lobata (Japanese arrowroot or kudzu).

A starchy substance obtained from the rhizomes of an arrowroot plant used as a thickener.

Source: wiktionary.org