trace1

verb

• 1find or discover by investigation:police are trying to trace a white van seen in the area
• find or describe the origin or development of:Bob’s book traces his flying career with the RAF

• 2follow or mark the course or position of (something) with one’s eye, mind, or finger:through the binoculars, I traced the path I had taken the night before
• take (a particular path or route):a tear traced a lonely path down her cheek

• 3copy (a drawing, map, or design) by drawing over its lines on a superimposed piece of transparent paper: trace a map of the world on to a large piece of paper
• draw (a pattern or line), especially with one’s finger or toe: she traced a pattern in the dirt with the toe of her shoe

• 4give an outline of:the article traces out some of the connections between education, qualifications, and the labour market

noun

• 1a mark, object, or other indication of the existence or passing of something:remove all traces of the old adhesive [mass noun]:the aircraft disappeared without trace
• a line or pattern displayed by an instrument to show the existence or nature of something which is being recorded or measured.
• a physical change in the brain presumed to be caused by a process of learning or memory.

• 2a very small quantity, especially one too small to be accurately measured:his body contained traces of amphetamines [as modifier]:trace quantities of PCBs
• a barely discernible indication of something:just a trace of a smile

• 3a procedure to investigate the source of something, such as the place from which a telephone call was made:we’ve got a trace on the call

• 4North American & West Indian a path or track.

• 5a line which represents the projection of a curve or surface on a plane or the intersection of a curve or surface with a plane.

• 6 Mathematics the sum of the elements in the principal diagonal of a square matrix.