The crossword solution for the term 'EVENING ON MT. ETNA' is SERA, which is a 4-letter word. SERA is an Italian word meaning 'EVENING' or 'NIGHT'. Mt. Etna is an active stratovolcano located on the east coast of Sicily, Italy. It is one of the most active volcanoes in the world and has been erupting for thousands of years. Therefore, the phrase 'EVENING on Mt. Etna' could refer to the time of day when the volcano is most active and visible.