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ob·sess

(əb-sĕs, ŏb-)

v. ob·sessed, ob·sess·ing, ob·sess·es

v. tr.

To preoccupy the mind of (someone) excessively.

v. intr.

To have the mind excessively preoccupied with a single emotion or topic: The conference organizer obsessed over the smallest of details.

[Latin obsidēre, obsess-, to beset, occupy : ob-, on; see OB- + sedēre, to sit; see sed- in the Appendix of Indo-European roots.]

ob·sessor n.

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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