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Inverse; inversely: obcordate.

[New Latin, short for obversē, obversely, from Latin obversus, past participle of obvertere, to turn toward : ob-, toward, against (from ob, toward, against, before; see epi in Indo-European roots) + vertere, to turn; see versus.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


inverse or inversely: obovate.
[from Old French, from Latin ob. In compound words of Latin origin, ob- (and oc-, of-, op-) indicates: to, towards (object); against (oppose); away from (obsolete); before (obstetric); down, over (obtect); for the sake of (obsecrate); and is used as an intensifier (oblong)]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ɔb, ɒb)
1. a river in the W Russian Federation in Asia, flowing NW to the Gulf of Ob. 2500 mi. (4025 km) long.
2. Gulf of, an inlet of the Arctic Ocean. ab. 500 mi. (800 km) long.


1. Also, obMed.
a. obstetrical.
b. obstetrician.
c. obstetrics.
2. off Broadway.


a prefix meaning “toward,” “to,” “on,” “over,” “against,” occurring in loanwords from Latin; used also, with the senses “reversely,” “inversely,” to form New Latin and English scientific terms: object; obligate; oblanceolate.
Also, o-, oc-, of-, op-.
[Middle English (< Old French) < Latin, representing ob (preposition); in some scientific terms, < New Latin, Latin ob-]


1. he died; she died.
[< Latin obiit]
2. incidentally.
[< Latin obiter]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in classic literature ?
With his disarming simplicity he made me ob- serve, as if it were a matter of some consequence, how strange it was that he should have spent the morning indoors at all.
"Ancient hauberk, date of the sixth century, time of King Arthur and the Round Table; said to have belonged to the knight Sir Sagramor le Desirous; ob- serve the round hole through the chain-mail in the left breast; can't be accounted for; supposed to have been done with a bullet since invention of firearms -- per- haps maliciously by Cromwell's soldiers."
Before the gray mists had been totally ob- literated by the sun rays, the regiment was march- ing in a spread column that was retiring carefully through the woods.