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col·lapse (kə-lăps)
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v. col·lapsed, col·laps·ing, col·laps·es
v.intr.
1. To fall down or inward suddenly; cave in.
2. To break down suddenly in strength or health and thereby cease to function: a monarchy that collapsed.
3. To fold compactly: chairs that collapse for storage.
v.tr.
To cause to fold, break down, or fall down or inward.
n.
1. The act of falling down or inward, as from loss of supports.
2. An abrupt failure of function, strength, or health; a breakdown.
3. An abrupt loss of perceived value or of effect: the collapse of popular respect for the integrity of world leaders.
[Latin collābī, collāps-, to fall together : com-, com- + lābī, to fall.]
col·laps′i·bili·ty n.
col·lapsi·ble adj.
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:

    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.

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