(lī′gāt″) [L. ligare, to tie, bind] To apply a ligature.
(lī-gā′shŏn) [L. ligatio, tying, binding] The application of a ligature.
rubber-band l. The application of a rubber band around a superficial bit of tissue, such as an internal hemorrhoid or an esophageal varix. Because its blood supply is thereby cut off, the tissue dies and sloughs. SYN: band l.
tubal l. A surgical method of contraception in which the fallopian tubes are severed and their cut ends are tied. It is used to prevent eggs, released from the ovaries, from entering the uterus where they might be penetrated by sperm. The procedure may be performed immediately after the delivery of a newborn (“postpartum tubal ligation”) or at another time preferred by the woman (“interval tubal ligation”). SYN: tubal occlusion.
(lig′ă-chŭr) [L. ligatura, a tying, binding] 1. Process of binding or tying. 2. A thread or wire for tying a blood vessel or other structure in order to constrict or fasten it. The cord or material used may be catgut, synthetic suture materials such as nylon or Dacron, polyglycolic acid, or natural fibers such as silk or cotton. Sometimes strips of fascia obtained from the patient are used as a ligature. SEE: suture. 3. A noose.
wire l. A soft, thin wire, elastic cord, or elastic loop used in orthodontics to anchor an arch wire or other dental devices or to tie two structures together.
(līt) Radiant electromagnetic energy limited to a wavelength of about 400 nm (extreme violet) to 770 nm (extreme red).
axial l. Light whose rays are parallel to each other and to the optic axis.
call l. A device used by a patient to signal his or her need for assistance from professional staff. It typically consists of a wireless remote control at the bedside, linked to a beeper, buzzer, cellular phone, chime, or light panel.
cold l. Any form of light that is not perceptibly warm. The heat of ordinary light rays is dissipated when they are passed through some medium such as quartz.
diffused l. Light rays broken by refraction.
intrinsic l. The sensation of light when there are no retinal stimuli to produce that sensation. SYN: idioretinal l.
oblique l. Light rays that strike a surface obliquely.
polarized l. Light in which waves vibrate in one direction only.
reflected l. Light rays thrown back by an illuminated object such as a mirror.
refracted l. Light rays bent from their original course.