Sapless and Weak-kneed

Sapless adjective - Destitute of sap and other vital juices; dry.

Weak-kneed and sapless are semantically related in bland topic. In some cases you can use "Weak-kneed" instead an adjective "Sapless".

Weak-kneed adjective - Lacking strength of will or character.

Sapless and weak-kneed are semantically related in bland topic. Sometimes you can use "Sapless" instead an adjective phrase "Weak-kneed".