Utilizing WordPress for Non-chronological Posts

i am building out my application on wordpress, and plan to have a search/browse interface where users can search for activities. i am writing activities each as a post, and applying metadata that tag the activities by various criteria. so in building this database of activities that are all equal candidates to return to a user – then, based on their search term or filter criteria, i want to display all the activities that match, most to least relevant. i’m concerned that wordpress defaults to chronological sort, and that the most recently posted activities will show up in search/browse results on page 1 most frequently. since chronology of when the activity was entered in the database is irrelevant, is there a way to avoid this default behavior? should i be using a certain plugin or method to fine tune my search results?