trace¹ / trās/ • v. [tr.] 1. find 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 Marines. ∎  follow 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.2. copy (a drawing, map, or design) by drawing over its lines on a superimposed piece of transparent paper. ∎  draw (a pattern or line), esp. with one's finger or toe. ∎  give an outline of: the article traces out some of the connections between education, qualifications, and the labor market.• n. 1. a mark, object, or other indication of the existence or passing of something: remove all traces of the old adhesive | the aircraft disappeared without trace. ∎  a beaten path or small road; a track. ∎  a physical change in the brain presumed to be caused by a process of learning or memory. ∎  a procedure to investigate the source of something, such as the place from which a telephone call was made, or the origin of an error in a computer program.2. a very small quantity, esp. one too small to be accurately measured: his body contained traces of amphetamines | [as adj.] trace quantities of PCBs. ∎  a slight indication or barely discernible hint of something: just a trace of a smile.3. a line or pattern displayed by an instrument using a moving pen or a luminous spot on a screen to show the existence or nature of something that is being investigated. ∎  a line that represents the projection of a curve or surface on a plane or the intersection of a curve or surface with a plane.4. Math. the sum of the elements in the principle diagonal of a square matrix.DERIVATIVES: trace·a·bil·i·ty / ˌtrāsəˈbilitē/ n.trace·a·ble adj.trace·less adj.trace² • n. each of the two side straps, chains, or ropes by which a horse is attached to a vehicle that it is pulling.

trace A recorded data-set for one channel. On a seismic-refraction record made for a 12-channel seismograph, each channel would provide one wave-form which, when viewed with the others, would give a seismic record. See also WIGGLE TRACE.

trace1 †path, course XIII; †series of footprints, track XIV; vestige, mark XVII. — (O)F., f. corr. vb. OF. tracier (mod. tracer) :- Rom. *tractiāre, f. L. tractus TRACT3.
So trace vb. A. proceed in a line or track; B. make marks on a plan, etc. XIV. — OF. Hence tracery †place for tracing XV; intersecting rib-work in a Gothic window XVII.

trace2 pair of ropes, etc. attached to the collar of a draught animal XIV; each of these XV. ME. trais, first as coll. pl., later as sg. — OF. trais, pl. of trait draught, harness-strap :- L. tractus draught, f. pp. stem of trahere draw.

TRACE (treɪs) task reporting and current evaluation
• Aeronautics test equipment for rapid automatic checkout evaluation