I. sap 1 /sæp/ BrE AmE noun
[ Language: Old English ; Origin: sæp ]
1 . [uncountable] the watery substance that carries food through a plant
2 . [countable] informal a stupid person who is easy to deceive or treat badly
II. sap 2 BrE AmE verb ( past tense and past participle sapped , present participle sapping ) [transitive]
to make something weaker or destroy it, especially someone’s strength or their determination to do something SYN weaken
sap sb’s strength/courage/energy
Her long illness was gradually sapping Charlotte’s strength.