obsess

Etymology

It is borrowed from Latin obsessus, the past participle of obsideō (“to sit at; to watch closely; to besiege, occupy”);^{[2][3][4][5][6][7]} the OED takes it from the participial stem obsess-.^[8] The Latin verb is formed from ob- (“against, opposite; on”) and sedeō (“to sit”),^[7][2][3][9] from Proto-Indo-European *sed- (“to sit”),^[2][7] so that it meant literally to sit opposite or down before a place.^{[2][3][9][10]} The OED compares Middle French obsesser (“to assail with temptations”) (1530).^[8] The same Latin verb gave obsession,^[3][9] and the root is that of sit and sedentary.^[3][6]

Earliest recorded meaning

Of an evil spirit, to control a person from outside; to haunt, harass or torment: 1440, in John Capgrave's Life of St Norbert.^[8] Barnhart and Etymonline begin instead with "to besiege", from 1503 or about 1500,^[3][2] and Etymonline dates the haunting sense to the 1530s.^[2] Merriam-Webster's first known use is in the 14th century, for the sense "to haunt, possess".^[4]

Semantic evolution

The military sense "to besiege" is recorded from 1503 to 1647.^[8][3] From 1531, in Elyot's Governour, the verb meant to beset or harass a person or the mind as a besieging army or an evil spirit would,^[8][3] and this led to the modern sense of filling someone's mind continually.^[8] The OED thinks the word perhaps fell out of use in the early 18th century and was revived in the 19th,^[8] and Hoad and Weekley also speak of a 19th-century revival.^[9][10] The psychological sense of being haunted by a fixed idea, according to Etymonline, developed gradually from the 1880s and became established in the 20th century; the Century Dictionary of 1895 still had only "besiege" and "to attack or plague from without".^[2] The Oxford Dictionary of English dates the current sense to the late 19th century.^[11] The intransitive use, to worry obsessively about something, began in the United States and is first recorded in the New York Times Magazine in 1977.^[8] A noun obsess, a siege, appears once, in Motteux's translation of Rabelais (1694).^[8]

Timeline

• 1440 – of an evil spirit, to haunt or torment a person.^[8]
• 1503 – to besiege (obsolete by 1647).^[8][3]
• 1531 – to beset or harass a person or the mind; later, to fill the mind continually.^[8][3]
• 1694 – noun, a siege or blockade (obsolete).^[8]
• 1977 – intransitive, to worry obsessively, first in the United States.^[8]

Meanings

Verb

1. To occupy someone's mind excessively and continually; to preoccupy: The unsolved case obsessed the detective for years.^[4][7][5][8]
2. To think or worry about something constantly, usually with about, on or over: He obsesses about every word in his speeches.^[7][4][5][8]
3. (archaic) Of an evil spirit, to haunt, beset or possess.^[4][8][12]
4. (obsolete, 1503–1647) To besiege.^[4][8][12]

Word family

• obsessor
• obsessingly
• obsessive

Related words

• obsession
• sit
• sedentary
• session
• siege

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
3. ^ a b c d e f g h i j Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
4. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
5. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins
6. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
7. ^ a b c d e The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
8. ^ a b c d e f g h i j k l m n o p q r Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
9. ^ a b c d Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
10. ^ a b Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
11. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
12. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press