These terms are from the FISH Archaeological Objects Thesaurus (Forum on Information Standards in Heritage - FISH).
| Term | Scope note | Term type | SENESCHAL URI | Other URI |
|---|---|---|---|---|
| Open Pit Mining | Narrow term | 71107 | - | |
| OPEN PLAN | A building plan where space is unconstrained by partitions. | Preferred term | 138030 | - |
| Open Prison | Narrow term | 92805 | - | |
| OPEN ROPEWALK | A long, narrow, rectangular plot of land used for the manufacture of rope. Usually walled, it may include small buildings and awnings at each end. Often attached to a warehouse. | Preferred term | 108113 | - |
| Open Settlement | Narrow term | 71108 | - | |
| OPEN SITE | A Palaeolithic or Mesolithic occupation site, excluding occupations of caves and rock shelters. Evidence for occupation may include traces of hearths and other structures. | Preferred term | 68990 | - |
| OPEN TRAINING PRISON | An institution for the imprisonment of prisoners who can be trusted to serve their sentence without likelihood of escape and of being a threat to the public. There is no physical barrier designed to prevent absconding. | Preferred term | 103814 | - |
| OPEN TRUSS | A truss which does not subdivide a space, as in the centre of a hall of two bays or in an undivided building such as a barn. | Preferred term | 138032 | - |
| OPEN WELL STAIRCASE | A staircase, usually rising through more than one storey, with a space at its centre around which the stair is carried by strings and newels. | Preferred term | 138033 | - |
| Open Work | Narrow term | 78148 | - | |
| Opencast Lead Workings | Narrow term | 71112 | - | |
| OPENCUT | A linear open working along a lode vein, worked directy from the surface. Survives as a gully or ravine, normally with closed ends. | Preferred term | 143712 | - |
| OPERA HOUSE | An often ornately decorated theatre for the performance of opera. | Preferred term | 69947 | - |
| OPERATING THEATRE | A room where surgical operations are performed. Originally in the form of a room with a raised table surrounded by tiered seating from where students could watch an operation or disection be performed. | Preferred term | 92806 | - |
| Operating Theatre Block | Narrow term | 92807 | - | |
| OPERATIONAL READINESS PLATFORM | An area on post-war military airfields for parking aircraft on quick reaction alert to allow immediate access to the runway. Abbreviation ORP. | Preferred term | 140449 | - |
| OPERATIONS BLOCK | A building of varying designs intended for directing military aviation operations. Normally associated with military airfields. | Preferred term | 140131 | - |
| OPERATIONS ROOM | A room used for directing military operations and exercises. | Preferred term | 160524 | - |
| Opercula | Narrow term | 159130 | - | |
| Ophthalmic Department | Narrow term | 92808 | - | |
| Ophthalmic Hospital | Narrow term | 92809 | - | |
| OPIUM PIPE | A pipe designed for smoking opium. | Preferred term | 95590 | - |
| OPPIDUM | An imprecise term used to describe large Iron Age settlements of town-like proportions. | Preferred term | 68744 | - |
| OPTICIANS | An establishment for the testing of eyesight, making up of optical prescriptions and the sale of spectacles. | Preferred term | 92810 | - |
| ORACLE BONE | A piece of bone used for divination. | Preferred term | 97508 | - |
| ORANGERY | A gallery or building in a garden, usually south facing, used for the growing of oranges and other fruit. | Preferred term | 69026 | - |
| ORANGES | Citrus fruit of a distinctive orange colour. | Preferred term | 79110 | - |
| ORATORY | A small private chapel in either a house or church. | Preferred term | 138034 | - |
| Oratory | Narrow term | 70112 | - | |
| ORCHARD | An enclosure used for the cultivation of fruit trees. | Preferred term | 68649 | - |
7771 - 7800 of 12,437 records.