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tran·spire (trăn-spīr)
v. tran·spired, tran·spir·ing, tran·spires
v. intr.
1. To come about; happen or occur.
2. To become known; come to light.
3. To give off vapor through plant stomata; undergo transpiration.
v. tr.
To give off (vapor) through the stomata of plant tissue.

[French transpirer, from Medieval Latin trānspīrāre : Latin trāns-, trans- + Latin spīrāre, to breathe.]

Usage Note: Transpire has been used since the mid-1700s in the sense “to become publicly known,” as in Despite efforts to hush the matter up, it soon transpired that the colonels had met with the rebel leaders. While this usage has been considered standard for generations, it is becoming uncommon and is not always recognized as correct. In our 2017 survey, 37 percent of the Usage Panel rejected it in the sentence quoted above. It might be better to use a synonym such as become known, leak out, or get around. · The more common use of transpire meaning “to happen or occur” has a more troubled history. Though it dates at least to the beginning of the 1800s, language critics have condemned it for more than one hundred years as both pretentious and unconnected to the word's original meaning, “to give off as vapor.” But there is considerable evidence that resistance to this sense of transpire is weakening. In our 1966 survey, only 38 percent of the Usage Panel found it acceptable; in 1988, 58 percent accepted it in the sentence All of these events transpired after last week's announcement, and by 2017, 83 percent accepted the same sentence. Nonetheless, some readers may find this usage pretentious or pompous; writers who wish to avoid giving such an impression can simply use happen, occur, or take place instead.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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:

    Indo-European Roots

    Semitic Roots

    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.