trace; vestige; mark; sign; evidence
operation scar; scar from an operation
rifling marks on a fired bullet
skid mark; tire mark; tyre mark
injection scar (e.g. injected drugs)
footprints (of a suspect at a crime scene)
linear mark; abrasion; scratch; streak
rifling marks on a fired bullet
ejector mark (on a cartridge)
extractor mark (on a cartridge)