The reason for choosing "secret meeting" as the most appropriate meaning of the word 'rendezvous' is based on its common usage and definition:

Rendezvous : A rendezvous is a planned meeting or gathering at a specific time and place, typically between individuals. The term is often used in the context of a secret or discreet meeting, especially in literature or espionage contexts. People may have a rendezvous to meet privately without others knowing, making it synonymous with a "secret meeting."

Options (2) "Misfortune," (3) "Agility," and (4) "Conversation" do not accurately represent the primary meaning of "rendezvous," which is related to meetings and gatherings rather than misfortune, agility, or conversation.