LOC
Abbreviation with 7 meanings
| Stands for | Level of consciousness |
|---|---|
| Meanings | 7 |
| Categories | Medical, Government & Politics, Business & Finance, Science & Engineering, Technology & Computing, Transportation & Travel |
LOC has seven meanings. The most common are Level of consciousness (patient assessment) and Loss of consciousness (neurology); it can also stand for Library of Congress, Line of credit, Locus of control, Lines of code and Localizer.
Meanings of LOC at a glance
| # | LOC stands for | Context |
|---|---|---|
| 1 | Level of consciousness | Medical › Patient Assessment |
| 2 | Loss of consciousness | Medical › Neurology |
| 3 | Library of Congress | Government & Politics › US Federal Agency |
| 4 | Line of credit | Business & Finance › Banking |
| 5 | Locus of control | Science & Engineering › Psychology |
| 6 | Lines of code | Technology & Computing › Programming |
| 7 | Localizer | Transportation & Travel › Aviation |
1. Level of consciousness
Medical · Patient Assessment Abbreviations
Degree of a patient's alertness and responsiveness, described with terms such as alert, lethargic, obtunded, stuporous or comatose, or scored with AVPU or the Glasgow Coma Scale. A drop in LOC is often the first sign of neurological deterioration.
Example: Decreased LOC, responds only to loud voice; glucose 42, D50 given.
Descriptive terms are interpreted differently by different staff, so documenting the stimulus needed and the response seen is more useful. In emergency and trauma notes LOC usually means loss of consciousness instead, as in "fall with LOC", so read the phrase in context.
2. Loss of consciousness
Medical · Neurology Abbreviations
Episode of being unresponsive and unaware of surroundings, documented after head injuries, falls, fainting and seizures. "No LOC" or "+LOC" is a key element of trauma and syncope histories because it affects decisions about imaging and observation.
Example: Restrained driver, rear-ended at low speed, no LOC, ambulatory at scene.
Duration matters: in concussion definitions, LOC lasting less than 30 minutes is compatible with mild traumatic brain injury, while longer periods indicate more severe injury. Witness accounts are important because patients cannot reliably report their own unconsciousness. In nursing assessments LOC more often means level of consciousness, so read the context.
3. Library of Congress
Government & Politics · US Federal Agency Abbreviations
National library of the United States and the research library of Congress, holding more than 170 million items in Washington. It houses the US Copyright Office and the Congressional Research Service and is led by the Librarian of Congress.
Example: Researchers can request rare maps through the LOC reading rooms on Capitol Hill.
Founded in 1800, it was rebuilt around Thomas Jefferson's personal library after British troops burned the Capitol in 1814. The Library of Congress Classification system is used by most US academic libraries. In finance LOC means line of credit, and in military usage line of communication.
4. Line of credit
Business & Finance · Banking Abbreviations
Flexible borrowing arrangement that lets a customer draw money up to a set limit, repay and borrow again, paying interest only on the amount used. Banks offer personal, business and home equity lines of credit.
Example: The business draws on its LOC each autumn to buy inventory before the holiday season.
A line of credit can be secured, for example by home equity (a HELOC), or unsecured, which usually carries a higher rate. Business lines are typically reviewed and renewed annually. In software, LOC means lines of code.
5. Locus of control
Science & Engineering · Psychology Abbreviations
Degree to which people believe outcomes in their lives are controlled by their own actions (internal locus) or by outside forces such as luck, fate or powerful others (external locus). An internal locus is linked to greater achievement motivation and health behaviors.
Example: Students with an internal LOC were more likely to attribute poor grades to lack of study.
Julian Rotter introduced the concept from social learning theory and published his Internal-External Control scale in 1966. Locus of control is related to, but distinct from, self-efficacy, the belief in one's ability to perform a specific task. In libraries and banking LOC has unrelated meanings.
6. Lines of code
Technology & Computing · Programming Abbreviations
A count of the lines in a program's source code, used as a rough measure of size, effort or productivity. Variants include SLOC (source lines of code) and KLOC (thousands of lines).
Example: The refactor deleted 12,000 LOC and the app got faster.
As a productivity metric it is widely criticized, because more code is not better; a remark often attributed to Bill Gates compares measuring programming progress by lines of code to measuring aircraft building progress by weight. Tools such as cloc count lines while excluding blanks and comments. In libraries LOC means the Library of Congress.
7. Localizer
Transportation & Travel · Aviation Abbreviations
ILS component that transmits a VHF signal aligned with the runway centerline, giving pilots lateral guidance on approach. A localizer-only approach, flown without the glideslope, is a nonprecision approach with higher minimums than a full ILS.
Example: Glideslope is out of service, so plan the LOC 16 approach with a minimum descent altitude of 640 feet.
Localizers operate between 108.10 and 111.95 MHz on odd-tenth frequencies, sharing the band with VORs. The needle is about four times as sensitive as a VOR needle, since full deflection is only about 2.5 degrees either side. A back course approach uses the signal transmitted off the opposite end of the antenna, which reverses needle sensing on older instruments.
Related abbreviations
More patient assessment abbreviations
- HR – Heart rate
- Ht – Height
- LAD – Lymphadenopathy
- LLE – Left lower extremity
- LUE – Left upper extremity
- MAE – Moves all extremities
- MAEW – Moves all extremities well
- MEWS – Modified Early Warning Score
See all 65 patient assessment abbreviations →
More neurology abbreviations
- LBD – Lewy body dementia
- LEMS – Lambert-Eaton myasthenic syndrome
- LKW – Last known well
- LMN – Lower motor neuron
- LP – Lumbar puncture
- LVO – Large vessel occlusion
- MCI – Mild cognitive impairment
- MG – Myasthenia gravis
See all 131 neurology abbreviations →
This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.