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pon·toon

(pŏn-tn)

Any of various floating structures, especially:

a. A flatbottom boat used to support a bridge.

b. A floating structure that serves as a dock.

c. Either of a pair of floats supporting a boat or seaplane.

[French ponton, from Old French, from Latin pontō, pontōn-, floating bridge, from pōns, pont-, bridge; see pent- in the Appendix of Indo-European roots.]

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pontoon

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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