ob·so·lete (ŏb′sə-lēt, ŏbsə-lēt′)
1. No longer in use: an obsolete word.
2. Outmoded in design, style, or construction: an obsolete locomotive.
3. Biology Vestigial or rudimentary, especially in comparison with related or ancestral species, as the tailbone of an ape. Used of an organ or other part of an organism.
tr.v. ob·so·let·ed, ob·so·let·ing, ob·so·letes
To cause to become obsolete: "The textbook publishers use every trick known to the marketing mind to obsolete their products year after year, thus closing off the possibility of second-hand sales" (Thomas Frank).
[Latin obsolētus, past participle of obsolēscere, to fall into disuse; see OBSOLESCENT.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.