(set phrase) Used as a filled pause to indicating thinking or pondering, not inviting hearer to participate.

(idiomatic, informal) Used to indicate that the speaker was in agreement with the preceding statement before it was made.

Used to propose marriage to someone

In confidence; used to impose an obligation to keep something being discussed secret.

(UK, slang, archaic) An expression of surprise.

(UK, slang, archaic) An expression of surprise.

(UK, slang, archaic) An expression of surprise.

(UK, vulgar, slang) Expression of surprise or amazement.

(Ireland, colloquial) Introduces a topic which is (actually or jocularly) grave or sensitive; listen up; I wanted to tell/ask you

(idiomatic, US) As an interrogatory, indicative of a nonchalant attitude towards potential criticism, not caring about what other people think, confident and self-possessed.