The term 'shine unsteadily' can be described by two crossword solutions: FLICKER (7 letters) and BLINK (5 letters). FLICKER is a verb that means to shine unsteadily, usually with a sudden change in brightness. It is often used to describe the light of a flame or candle. BLINK is also a verb that means to shine unsteadily, but it is usually used to describe the light from a lamp or other electric source. Both words are used to describe a light that is not steady or constant.