to be missing or unaccounted for

to follow someone's physical tracks, shadow, or tail someone secretly

to track, trace, or follow up on the path, development, or progress of someone or something

the location or movement patterns of a person

the visible sign of a person or thing's existence in a particular place, often used in the context of their disappearance

a sign or vestige indicating the presence or existence of someone or something

(idiom) to disappear without a trace

a person who has disappeared or whose whereabouts are unknown.

a sign or evidence of someone or something's presence or whereabouts

a case involving the disappearance of one or more people

a device used for monitoring and recording the location or movement of a person, vehicle, or object

to come and go without a trace

to go into hiding; to conceal one's tracks

to follow along behind someone (formal writing)

a person's background or the full details and origins of a matter

to disperse and flee, leaving no trace

no trace to be seen

(computing) ray tracing

without a trace

To come and go without a trace.

to abscond without leaving a trace

to disappear or hide oneself (often unexpectedly or as a joke)

to hide; to conceal one's tracks

tracker (device)

(law) to stalk (someone)

Mizongyi, Mizong, or My Jhong Law Horn; a style of Chinese martial art known as "Lost Track Fist".

tracking number (of a package shipment)

A longitudinal research method involving repeated observations of subjects over an extended period.

gone without a trace