| glaucoma, open-angle | Glaucoma in which the angle of the anterior chamber is open and the trabecular meshwork does not encroach on the base of the iris. (12 Dec 1998) |
|---|---|
| semi-open anaesthesia | <anaesthetics> Inhalation anaesthesia in which a portion of inhaled gases is derived from an anaesthesia circuit while the remainder consists of room air. (05 Mar 2000) |
| open | Open or unobstructed space; clear land, without trees or obstructions; open ocean; open water. "To sail into the open." "Then we got into the open." (W. Black) In open, in full view; without concealment; openly. 1. Free of access; not shut up; not closed; affording unobstructed ingress or egress; not impeding or preventing passage; not locked up or covered over; applied to passageways; as, an open door, window, road, etc.; also, to inclosed structures or objects; as, open houses, boxes, baskets, bottles, etc.; also, to means of communication or approach by water or land; as, an open harbor or roadstead. "Through the gate, Wide open and unquarded, Satan passed." (Milton) Also, figuratively, used of the ways of communication of the mind, as by the senses; ready to hear, see, etc.; as, to keep one's eyes and ears open. "His ears are open unto their cry." (Ps. Xxxiv. 15) 2. Free to be used, enjoyed, visited, or the like; not private; public; unrestricted in use; as, an open library, museum, court, or other assembly; liable to the approach, trespass, or attack of any one; unprotected; exposed. "If Demetrius . . . Have a matter against any man, the law is open and there are deputies." (Acts xix. 33) "The service that I truly did his life, Hath left me open to all injuries." (Shak) 3. Free or cleared of obstruction to progress or to view; accessible; as, an open tract; the open sea. 4. Not drawn together, closed, or contracted; extended; expanded; as, an open hand; open arms; an open flower; an open prospect. "Each, with open arms, embraced her chosen knight." (Dryden) 5. Hence: Without reserve or false pretense; sincere; characterised by sincerity; unfeigned; frank; also, generous; liberal; bounteous; applied to personal appearance, or character, and to the expression of thought and feeling, etc. "With aspect open, shall erect his head." (Pope) "The Moor is of a free and open nature." (Shak) "The French are always open, familiar, and talkative." (Addison) Not concealed or secret; not hidden or disguised; exposed to view or to knowledge; revealed; apparent; as, open schemes or plans; open shame or guilt. "His thefts are too open." (Shak) "That I may find him, and with secret gaze Or open admiration him behold." (Milton) 6. Not of a quality to prevent communication, as by closing water ways, blocking roads, etc.; hence, not frosty or inclement; mild; used of the weather or the climate; as, an open season; an open winter. 7. Not settled or adjusted; not decided or determined; not closed or withdrawn from consideration; as, an open account; an open question; to keep an offer or opportunity open. 8. Free; disengaged; unappropriated; as, to keep a day open for any purpose; to be open for an engagement. 9. Uttered with a relatively wide opening of the articulating organs; said of vowels; as, the an far is open as compared with the a in say. Uttered, as a consonant, with the oral passage simply narrowed without closure, as in uttering s. 10. Not closed or stopped with the finger; said of the string of an instrument, as of a violin, when it is allowed to vibrate throughout its whole length. Produced by an open string; as, an open tone. The open air, the air out of doors. Open chain. <chemistry> See Closed chain, under Chain. <physics> Open circuit, a roof of which the constructional parts, together with the under side of the covering, or its lining, are treated ornamentally, and left to form the ceiling of an apartment below, as in a church, a public hall, and the like. Open vowel or consonant. See Open. Open is used in many compounds, most of which are self-explaining; as, open-breasted, open-minded. Synonym: Unclosed, uncovered, unprotected, exposed, plain, apparent, obvious, evident, public, unreserved, frank, sincere, undissembling, artless. See Candid, and Ingenuous. Origin: AS. Open; akin to D. Open, OS. Opan, G. Offan, Icel. Opinn, Sw. Oppen, Dan. Aaben, and perh. To E. Up. Cf. Up, and Ope. Source: Websters Dictionary (01 Mar 1998) |
| open-angle glaucoma | <ophthalmology> A disorder which is characterised by increased pressure within the eyeball. This occurs secondary to the chronic blockage of normal fluid circulation within the eye. Increased pressure within the eye can cause damage to the optic nerve and eventual blindness. Glaucoma is the leading cause of blindness. Symptoms include decreased vision, halos around lights (worse at night) and mild chronic headaches. Treatment is generally with beta-blocker eyedrops. Synonym: chronic glaucoma, compensated glaucoma, simple glaucoma, glaucoma simplex. (22 Sep 2002) |
| open biopsy | <surgery> Surgical incision or excision of the region from which the biopsy is taken. (05 Mar 2000) |
| open bite | <dentistry> A malocclusion in which the teeth do not close or come together in the front of your mouth. (08 Jan 1998) |
| open chain compound | An organic compound in which the chain does not form a ring. Synonym: aliphatic compound, open chain compound. (05 Mar 2000) |
| open chest massage | Rhythmic manual compression of the ventricles of the heart with the hand inside the thoracic cavity. (05 Mar 2000) |
| open circuit method | A method for measuring oxygen consumption and carbon dioxide production by collecting the expired gas over a known period of time and measuring its volume and composition. (05 Mar 2000) |
| open comedo | A comedo with a wide opening on the skin surface capped with a melanin-containing blackened mass of epithelial debris. Synonym: blackhead. (05 Mar 2000) |
| open cordotomy | See: cordotomy. (05 Mar 2000) |
| open dislocation | A dislocation complicated by a wound opening from the surface down to the affected joint. Synonym: compound dislocation. (05 Mar 2000) |
| open drainage | Drainage allowing air to enter. (05 Mar 2000) |
| open drop anaesthesia | Inhalation anaesthesia by vaporization of a liquid anaesthetic placed drop by drop on a gauze mask covering the mouth and nose. (05 Mar 2000) |
| open flap | A flap in which during transfer the pedicle is left flat or open, i.e., untubed. Synonym: open flap. (05 Mar 2000) |