The term 'chance upon' can be broken down into five crossword solutions: ENCOUNTER (9 letters), MEET (4 letters), LUCK (4 letters), FIND (4 letters), and runinto (7 letters). ENCOUNTER means to come across something or someone unexpectedly, while MEET is to come into the presence of someone. LUCK is a chance happening that brings good fortune, and FIND is to discover something that was previously lost or unknown. Finally, runinto is to come across someone or something unexpectedly. All of these words are related to the term 'chance upon, ' which means to come across something or someone unexpectedly.