The term 'brighten up' can be broken down into six crossword solutions: CLEAR (5 letters), LIVEN (5 letters), JAZZ (4 letters), ILLUMINE (8 letters), PERK (4 letters), and PLEASE (6 letters). CLEAR means to make something free from obstruction or confusion, while LIVEN means to make something more lively or cheerful. JAZZ is a type of music characterized by improvisation and syncopated rhythms, while ILLUMINE means to light up or make something brighter. PERK means to become more lively or cheerful, and PLEASE is an expression of politeness used when asking for something. SATISFY means to meet the needs or expectations of someone. All of these words can be used to describe the act of brightening up something, whether it be a person's mood, a room, or an atmosphere.