The noun pledge has 4 senses (no senses from tagged texts)
1. pledge -- (a deposit of personal property as security for a debt; "his saxophone was in pledge")
2. pledge -- (someone accepted for membership but not yet fully admitted to the group)
3. pledge, toast -- (a drink in honor of or to the health of a person or event)
4. assurance, pledge -- (a binding commitment to do or give or refrain from something; "an assurance of help when needed"; "signed a pledge never to reveal the secret")
Overview of verb pledge
The verb pledge has 5 senses (first 1 from tagged texts)
1. (3) pledge, plight -- (promise solemnly and formally; "I pledge that will honor my wife")
2. pledge, subscribe -- (pay (an amount of money) as a contribution to a charity or service, especially at regular intervals; "I pledged $10 a month to my favorite radio station")
3. toast, drink, pledge, salute, wassail -- (propose a toast to; "Let us toast the birthday girl!"; "Let's drink to the New Year")
4. pledge -- (give as a guarantee; "I pledge my honor")
5. pledge -- (bind or secure by a pledge; "I was pledged to silence")