Return to the home page.

Expand/collapse menu.

Visit Our Sites

Unabridged Dictionary

Learner's Dictionary

Word Central for Kids

Collegiate Dictionary

Expand/collapse menu.

Premium Services

Unabridged Dictionary

Collegiate Dictionary

Encyclopedia Britannica

Institutional Subscriptions

Expand/collapse menu.

Expand/collapse menu.

Word of the Day

Subscriber Help

Expand/collapse menu.

More Word Games

Daily Crosswords

Expand/collapse menu.

Open Dictionary

Alphabetical Browse

Browse Categories

Submit an Entry

Expand/collapse menu.

Spelling Bee Hive

Hive Headquarters

Spelling Champion

Spelling Reform

Expand/collapse menu.

Word for the Wise

Today's Broadcast

Expand/collapse menu.

Books and CD-Roms

Online Services

Palm and Pocket PC

Expand/collapse menu.

Looking Up a Word

Citing the Dictionary

Audio Pronunciations

Word Games Help

Expand/collapse menu.

Merriam-Webster FAQ

Advertising Info

Copyright Notice

Also Visit:
Unabridged
Visual

ESL:
Learner's
for Kids:
Word Central
Spell It!

Browse the Medical Dictionary:: A; B; C; D; E; F; G; H; I; J; K; L; M; N; O; P; Q; R; S; T; U; V; W; X; Y; Z; #

tracer

Main Entry:: trac·er
Pronunciation:: \ˈtrā-sər\
Function:: noun

: a substance used to trace the course of a process; specifically : a labeled element or atom that can be traced throughout chemical or biological processes by its radioactivity or its unusual isotopic mass

Learn more about "tracer" and related topics at Britannica.com

Pronunciation Symbols