Akademik

crystal
A solid of regular shape and, for a given compound, characteristic angles, formed when an element or compound solidifies slowly enough, as a result either of freezing from the liquid form or of precipitating out of solution, to allow the individual molecules to take up regular positions with respect to one another. [G. krystallos, clear ice, c.]
- asthma crystals SYN: Charcot-Leyden crystals.
- blood crystals SYN: hematoidin.
- Böttcher crystals small crystals observed microscopically in prostatic fluid that is treated with a drop or two of 1% solution of ammonium phosphate.
- Charcot-Leyden crystals crystals in the shape of elongated double pyramids, formed from eosinophils, found in the sputum in bronchial asthma and in other exudates or transudates containing eosinophils. SYN: asthma crystals, Charcot-Neumann crystals, Charcot-Robin crystals, Leyden crystals.
- Charcot-Neumann crystals SYN: Charcot-Leyden crystals.
- Charcot-Robin crystals SYN: Charcot-Leyden crystals.
- chiral c. an enantiomorphic, dysymmetric, optically active c..
- chlorohemin crystals SYN: Teichmann crystals.
- clathrate c. latticelike arrangement of molecules of one substance surrounding molecules of another substance.
- ear crystals SYN: otoliths.
- Florence crystals brown rhombic crystals formed at the interface between a drop of Lugol solution and a drop of fluid that contains semen; not a specific test for the latter.
- hematoidin crystals SYN: hematoidin.
- hydrate c. one of several possible microstructural arrangements of water molecules based on intermolecular forces; suggested as being involved in the mode of action of inhalation anesthetics.
- knife-rest c. a c. of ammoniomagnesium phosphate found in alkaline urine.
- Leyden crystals SYN: Charcot-Leyden crystals.
- Lubarsch crystals intracellular crystals in the testis resembling sperm crystals.
- sperm c., spermin c. a c. of spermin phosphate found in the semen; possibly identical to Böttcher crystals.
- Teichmann crystals rhombic crystals of hemin; used in microscopic detection of blood. See hemin. SYN: chlorohemin crystals.
- thorn apple crystals ammonium urate crystals in the shape of rounded bodies with many projecting points.
- twin c. two crystals that have grown together along a common face.
- Virchow crystals yellow-brown, amber, or burnt orange crystals of hematoidin, frequently observed in extravasated blood in tissues.
- whetstone crystals xanthine crystals occasionally observed in urine.

* * *

crys·tal 'kris-təl n
1) a body that is formed by the solidification of a chemical element, a compound, or a mixture and has a regularly repeating internal arrangement of its atoms and often external plane faces
2) ice (2) broadly methamphetamine in any form when used illicitly
crystal adj

* * *

crys·tal (krisґtəl) [Gr. krystallos ice] a homogeneous angular solid formed from a chemical element, compound, or isomorphous mixture, having a definite form in which the ultimate units from which it is built up are systematically arranged.

Medical dictionary. 2011.