Glossary
L
label
Pieces of paper, leather, fabric, or small tablets inscribed and affixed to something for identification or description. In the context of bookbinding, refers specifically to paper or other material separate from that used to cover a book, on which the author's name and the title are printed or engraved and glued to the spine or front board.
laboratory
Rooms, buildings, or groups of buildings equipped with apparatus for scientific experiments or other research, testing, and investigations.
laboratory apparatus
A term used to refer to any equipment commonly used in a scientific laboratory. Includes flasks, beakers, test tubes and measuring cylinders.
lacquer
A varnish that dries by the process of evaporation to provide a hard, protective finish.
lactic
relating to milk
lactometer
A type of hydrometer for measuring lactose sugars in milk.
lancets
A surgical instrument of various forms, commonly sharp-pointed and two-edged. The lancet is used in venesection (the act of opening a vein for bloodletting), and in opening abscesses.
larva
The newly hatched, wingless, often wormlike form of many insects before their transition to an adult form.
laryngeal syringe
syringe used to apply medications and treatments to the larynx
laryngoscope
An instrument used to examine the larynx
larynx
An organ in the neck of mammals involved in protection of the trachea (windpipe) and sound production.
laudanum
A herbal preparation of opium. It is made by mixing ethanol with opium. In the 1800s, laudanum was prescribed by many doctors to reduce pain and aid sleep.
lavatory paper
Paper for cleansing oneself after defacation or urination
lavatory seat cover
Covers used to place over public toilet seats for personal hygiene.
laxative
An agent that acts to encourage evacuation of the bowels
leaflet
Use for small printed works consisting of one sheet folded and not stitched or bound. For larger printed works, but generally of fewer than 80 pages, often with paper covers, use "pamphlets."
leech
A type of worm that possesses suckers at both ends of its body. Formerly widely used for letting blood, the medicinal leech may now be used following microsurgery to encourage the growth of new capillaries. Leeches are found in tropical forests, grasslands and in water.
leech box
Box for containing and/or transporting leeches.
leech jar
Jar for keeping leeches in with pierced cover
lenticular
Referring to or shaped like a lentil, such as the lens of the eye
leper clapper
A type of rattle that people with leprosy were forced to carry in the 1600s. The noise made by the clapper warned people to avoid the infected person.
leprosy
A chronic disease that affects the skin, mucous membrane and nerves. It is now confined mainly to the tropics and is transmitted by direct contact. Previously a widely feared disease, leprosy is not highly infectious.
lesion
An abnormal structural change in a body part
letter - correspondence
Pieces of correspondence that are somewhat more formal than memoranda or notes, usually on paper and delivered.
leucorrhoea
A discharge of a white, yellowish, or greenish, viscid mucus, resulting from inflammation or irritation of the membrane lining the genital organs of the female
leukaemia
A cancer of the blood or bone marrow. Leukaemia is caused by an abnormal growth in numbers of cells, usually white blood cells. It is a broad term covering a number of different disorders.
Leyden jar
Earliest and simplest device for storing static electricity, developed c.1745 in Leyden, Holland. The original electrical capacitor, it consists of a foil-lined glass jar partly filled with water and closed with a cork through which protrudes a brass rod wired to the foil. To charge the jar, friction is applied to the tip of the rod
libation cup
A libation is an offering of wine, milk, honey, or oil that was poured to honour the dead or to praise the gods.
lice comb
Comb used to detect and remove head lice and their eggs from hair.
ligature
A thread or string for tying the blood vessels, particularly the arteries, to prevent bleeding. The word ‘ligature’ can also refer to the action or result of binding or tying, e.g. the ligature of an artery.
linear dividing engine
A machine for accurately dividing the linear scales of various measuring instruments, such as thermometers, and for producing glass graticules.
lithograph
Prints made using the process of lithography - a method for printing using a plate or stone with a completely smooth surface.
lithotome
instrument used for cutting the bladder in operations for removal of stones (calculous concretions); from Greek: lithos (stone) and thomos (cut)
lithotomy
The operation of cutting stones from the hollow organs, such as the kidney or bladder.
lithotomy crutch
to hold the patient in the lithotomy position
lithotomy instrument set
Instrument set for performing lithotomies - The operation, art, or practice of cutting for stone in the bladder.
lithotomy staff
The grooved director for the gorget, or knife, used in cutting for stone in the bladder
lithotrite
a mechanical instrument used to crush urinary stones
lithotrity
the operation of breaking a stone in the bladder into small pieces to be passed
lithotrity instrument set
used to perform lithotrity
litmus paper
Litmus is a water-soluble mixture of different dyes extracted from lichen. It is absorbed on to filter paper and used to test for acids and alkalis – indicated by a change in the colour of the litmus paper.
liver
Organ that plays a major role in metabolism, digestion, and elimintation of substances in the body.In the warm-blooded animals the liver is usually of a dark reddish-brown colour. In man it is situated below the diaphragm, and is divided by fissures into five lobes. A human can last only 24 hours without liver function.
lizard
A broad group of reptile found on every continent; there are 20 families, c.3000 species. Most lizards have four limbs, external ears, and a tail. Many lizards can shed their tails in order to escape from predators, although this trait is not universal. Vision, including color vision, is particularly well developed in lizards, and most communicate with body language or bright colors on their bodies as well as via pheromones.
lobotomy
A controversial surgical treatment to severe the nerves to the frontal lobe of the brain (responsible for attention, short-term memory and activities requiring planning and organization). It was used to treat severe mental illnesses but is now no longer used.
local anaesthetic
A drug that reduces or removes sensations from one area of the body.
lodestone
A piece of magnetic iron ore, which can act like a compass needle.
log book
A book used to determine the distance a ship travels within a certain amount of time.
logarithmic scale
A method of representing numbers (certainly positive and usually greater than or equal to 1) by points on a line.
long-sightedness
A defect of the eye where images are produced behind the retina rather than on it. This causes objects that are further away from the viewer to appear blurred. Long-sightedness is usually treated with glasses or corrective surgery.
lorgnettes
A type of spectacles usually hand held with a long ornate handle.
lower-body negative pressure box
A device used to apply negative pressure to the lower body (from the chest downwards). Used to simulate the G force experienced by pilots and astronauts.
lozenge
A small medicated sweet to be dissolved slowly in the mouth. Lozenges are intended to sooth and lubricate the throat.
LP record
A type of long-playing record pressed in vinyl
lumbago
A term used to describe mild to severe lower back pain.
lung
one of the pair of organs of respiration, situated in the chest cavity on either side of the heart and enclosed by a serous membrane (see plural).
lymph
Clear, slightly yellowish fluid derived from the blood and similar in composition to plasma. Lymph conveys white blood cells and some nutrients to the tissues.