OP

Multiple Entries:
  OP    op    Op.    o.p.    ob-    op-  

Concise Oxford English Dictionary © 2008 Oxford University Press:
OP

▶abbreviation

• 1 observation post.

• 2 (in the theatre) opposite prompt, the offstage area to the right of an actor.

• 3 organophosphate(s).

• 4

  ■ (in the Roman Catholic Church) Order of Preachers (Dominican).

  ■[L. Ordo Praedicatorum.]

Concise Oxford English Dictionary © 2008 Oxford University Press:
op/ɒp/

▶noun informal

• 1 a surgical operation.

• 2 (ops) military operations.

• 3 a radio or telephone operator.

Concise Oxford English Dictionary © 2008 Oxford University Press:
Op. (also op.)

▶abbreviation Music (before a number given to each work of a particular composer) opus.

Concise Oxford English Dictionary © 2008 Oxford University Press:
o.p.

▶abbreviation

• 1 (of a book) out of print.

• 2 (of alcohol) overproof.

Concise Oxford English Dictionary © 2008 Oxford University Press:
ob- /ɒb/ (also oc- before c; of- before f; op- before p)

▶prefix forming words of mainly Latin origin, meaning.

• 1 to, towards: obverse.

• 2 against; blocking: opponent.

  ■ concealment: occult.

• 3 finality or completeness: obsolete.

• 4 technical in a direction or manner contrary to the usual: obconical.

– origin from L. ob ‘towards, against, in the way of’.

Concise Oxford English Dictionary © 2008 Oxford University Press:
op-/ɒp/

▶prefix variant spelling of ob-. assimilated before p (as in oppress, oppugn).