Merest Trace is a term used to describe something that is barely visible or detectable. The crossword solutions for this term are WISP (4 letters), SCINTILLA (9 letters), and SHRED (5 letters). WISP refers to a small amount of something, such as smoke or vapor, that is barely visible. SCINTILLA is a very small amount of something, often used to describe a trace of an emotion or feeling. Finally, SHRED is a term used to describe something that has been torn into small pieces, often so small that it is barely visible.