音标：['treisә]
n. 追踪者, 描图者, 描绘工具
【计】 跟踪程序
【化】 示踪剂
【医】 示踪器; 示踪物; 描记器
在线英汉词典

tracer的短语、例句：

tracer n 1 person or thing that traces 追踪者; 追踪装置; 描摹者; 描摹工具. 2 bullet or shell whose course is made visible by a line of smoke, etc left behind it 曳光弹
[attrib 作定语] tracer bullets 曳光弹. 3 radioactive substance whose course through the human body, etc can be traced by the radiation it produces, used for investigating a chemical or biological process 示踪物.