1. A time limit, as for payment of a debt or completion of an assignment.
2. A boundary line in a prison that prisoners can cross only at the risk of being shot.
tr.v. dead·lined, dead·lin·ing, dead·lines
To govern by setting a time limit: "He was never going to be deadlined by a day, or even a month" (New Yorker).
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
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.