| OF | |
| abbr. f.trade. | orange flake |
| abbr. oil | ocean freight; oceanographic facility; oil-fired; open fracture |
| abbr. textile | olefin fiber; ooze finish; open fabric; open flame; Oxidationsfarbstoff |
| error | |
| IT | A deviation from accuracy or correctness |
| law abbr. | e.; er. |
| metrol. | Of measurement: result of a measurement minus a true value of the measurand |