Some words (verbs and nouns) can get up- or down- attached before them to get new meaning. For example, Grade becomes upgrade or downgrade. Vote becomes upvote or downvote. Load becomes upload or ...
To illustrate a simple example, when I encounter the word "claustrophobia", what I already knew is the left part "claustro-" means "small and enclosed", and I want to discover if "-phobia" has a fixed ...