"Your quickapprovalof the proposal is essential for us to proceed with the plan." Here, the underlined word is -

• Your quick approval of the proposal is essential for us to proceed with the plan." Here, the underlined word is - a noun.

• Approval (noun)

English Meaning: an act or instance of approving something.
Bangla Meaning: অনুমোদন; সমর্থন।

Other forms:
→ Approve (verb),
→ Approved (adjective),
→ Approvedly (adverb),
→ Approvedness (noun),
→ Approvingly (adverb).

Source: dictionary.com