piping

Concise Oxford English Dictionary © 2008 Oxford University Press:
piping/ˈpʌɪpɪŋ/

▶noun

• 1 lengths of pipe.

• 2 thin lines of icing or cream, used to decorate cakes and desserts.

• 3 thin cord covered in fabric, used for decoration and to reinforce seams.

• 4 the action or art of playing a pipe or pipes.

– phrases
piping hot (of food or water) very hot. [so called because of the whistling sound made by very hot liquid or food.]