The term 'impermanent' is used to describe something that is not permanent or lasting. This can be seen in the crossword solutions provided, such as 'EPHEMERAL' (9 letters), which means lasting for a very short time, 'INTERIM' (7 letters), meaning lasting for a limited period of time, 'moving' (6 letters), which implies something that is constantly changing, 'PASSING' (7 letters), which suggests something that is FLEETING, 'FUGITIVE' (8 letters), which suggests something that is FLEETING and hard to capture, 'FLEETING' (8 letters), which implies something that is BRIEF and quickly PASSING, 'BRIEF' (5 letters), which implies something that is short-lived, 'MORTAL' (6 letters), which implies something that is subject to death or destruction, 'FINITE' (6 letters), which implies something that has an end, 'erasable' (8 letters), which implies something that can be removed or erased, 'TEMPORAL' (8 letters), which implies something that is related to time, 'TRANSIENT' (9 letters), which implies something that is TEMPORARY and PASSING, 'TRANSITORY' (10 letters), which implies something that is short-lived, 'daytoday' (8 letters), which implies something that is ordinary and mundane, and 'TEMPORARY' (9 letters), which implies something that is not lasting. All of these words are used to describe something that is not permanent or lasting.