1. Roman Mythology The goddess of the hearth, worshiped in a temple containing the sacred fire tended by the vestal virgins.
2. The brightest of the asteroids and the second most massive object in the asteroid belt after the dwarf planet Ceres.
[Latin; see wes-1 in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.