n. Abbr. bb
1. A friction-reducing bearing consisting essentially of a ring-shaped track containing freely revolving hard metal balls against which a rotating shaft or other part turns.
2. A hard ball used in such a bearing.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
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