Discharge pipe and Hydrant

Discharge pipe noun - A pipe through which fluids can be discharged.

Hydrant and discharge pipe are semantically related. In some cases you can replace term "Hydrant" with "Discharge pipe", this terms are similar.

Hydrant noun - A discharge pipe with a valve and spout at which water may be drawn from the mains of waterworks.

Discharge pipe and hydrant are semantically related. Sometimes you can use "Discharge pipe" instead a noun "Hydrant".