What's the difference between cover and sheath?

Cover


Definition:

  • (v. t.) To overspread the surface of (one thing) with another; as, to cover wood with paint or lacquer; to cover a table with a cloth.
  • (v. t.) To envelop; to clothe, as with a mantle or cloak.
  • (v. t.) To invest (one's self with something); to bring upon (one's self); as, he covered himself with glory.
  • (v. t.) To hide sight; to conceal; to cloak; as, the enemy were covered from our sight by the woods.
  • (v. t.) To brood or sit on; to incubate.
  • (v. t.) To shelter, as from evil or danger; to protect; to defend; as, the cavalry covered the retreat.
  • (v. t.) To remove from remembrance; to put away; to remit.
  • (v. t.) To extend over; to be sufficient for; to comprehend, include, or embrace; to account for or solve; to counterbalance; as, a mortgage which fully covers a sum loaned on it; a law which covers all possible cases of a crime; receipts than do not cover expenses.
  • (v. t.) To put the usual covering or headdress on.
  • (v. t.) To copulate with (a female); to serve; as, a horse covers a mare; -- said of the male.
  • (n.) Anything which is laid, set, or spread, upon, about, or over, another thing; an envelope; a lid; as, the cover of a book.
  • (n.) Anything which veils or conceals; a screen; disguise; a cloak.
  • (n.) Shelter; protection; as, the troops fought under cover of the batteries; the woods afforded a good cover.
  • (n.) The woods, underbrush, etc., which shelter and conceal game; covert; as, to beat a cover; to ride to cover.
  • (n.) The lap of a slide valve.
  • (n.) A tablecloth, and the other table furniture; esp., the table furniture for the use of one person at a meal; as, covers were laid for fifty guests.
  • (v. i.) To spread a table for a meal; to prepare a banquet.

Example Sentences:

  • (1) In a debate in the House of Commons, I will ask Britain, the US and other allies to convert generalised offers of help into more practical support with greater air cover, military surveillance and helicopter back-up, to hunt down the terrorists who abducted the girls.
  • (2) Photograph: Guardian The research also compiled data covered by a wider definition of tax haven, including onshore jurisdictions such as the US state of Delaware – accused by the Cayman islands of playing "faster and looser" even than offshore jurisdictions – and the Republic of Ireland, which has come under sustained pressure from other EU states to reform its own low-tax, light-tough, regulatory environment.
  • (3) The surface of all cells was covered by a fuzzy coat consisting of fine hairs or bristles.
  • (4) Five patients have been examined by defecography before and four after closure of a loop ileostomy performed to cover healing of the pouch and ileoanal anastomoses.
  • (5) A failure to reach a solution would potentially leave 200,000 homes without affordable cover, leaving owners unable to sell their properties and potentially exposing them to financial hardship.
  • (6) It was an artwork that fired the imaginations of 2 million visitors who played with, were provoked by and plunged themselves into the curious atmosphere of The Weather Project , with its swirling mist and gigantic mirrors that covered the hall's ceiling.
  • (7) But because current donor contributions are not sufficient to cover the thousands of schools in need of security, I will ask in the commons debate that the UK government allocates more.
  • (8) The degree of infection and incidence of different genera covering the same period were identical in both series.
  • (9) At first it looked as though the winger might have shown too much of the ball to the defence, yet he managed to gain a crucial last touch to nudge it past Phil Jones and into the path of Jerome, who slipped Chris Smalling’s attempt at a covering tackle and held off Michael Carrick’s challenge to place a shot past an exposed De Gea.
  • (10) The Sports Network broadcasts live NHL, Nascar, golf and horse racing – having also recently purchased the rights for Formula One – and will show 154 of the 196 games that NBC will cover.
  • (11) As to complications they recorded in one case mucosal bleeding after gastrofiberoptic polypectomy and in one case a covered perforation of the sigmoid at the site of colonoscopic polypectomy.
  • (12) The pressure is ramping up on Asda boss Andy Clarke, who next week will reveal the chain’s sales performance for the quarter covering Christmas.
  • (13) This week MediaGuardian 25, our survey of Britain's most important media companies, covering TV, radio, newspapers, magazines, music and digital, looks at BSkyB.
  • (14) When allegations of systemic doping and cover-ups first emerged in the runup to the 2013 Russian world athletics championships, an IOC spokesman insisted: “Anti-doping measures in Russia have improved significantly over the last five years with an effective, efficient and new laboratory and equipment in Moscow.” London Olympics were sabotaged by Russia’s doping, report says Read more We now know that the head of that lauded Moscow lab, Grigory Rodchenko, admitted to intentionally destroying 1,417 samples in December last year shortly before Wada officials visited.
  • (15) Chapman and the other "illegals" – sleeper agents without diplomatic cover – seem to have done little to harm American national security.
  • (16) This hydrostatic pressure may well be the driving force for creating channels for acid and pepsin to cross the mucus layer covering the mucosal surface.
  • (17) A retrospective study of autopsy-verified fatal pulmonary embolism at a department of infectious diseases was carried out, covering a four-year period (1980-83).
  • (18) Over the same period, breeding in drums dropped from 14%-25% to 4.7%, even though the drums were not treated or covered.
  • (19) The study covered 500 children from Warsaw's primary schools--250 children aged 6-8 years and 250 aged 13-15 years.
  • (20) The smaller interfaces cover about 700 A2 of the subunit surface.

Sheath


Definition:

  • (n.) A case for the reception of a sword, hunting knife, or other long and slender instrument; a scabbard.
  • (n.) Any sheathlike covering, organ, or part.
  • (n.) The base of a leaf when sheathing or investing a stem or branch, as in grasses.
  • (n.) One of the elytra of an insect.

Example Sentences:

  • (1) The oral nerve endings of the palate, the buccal mucosa and the periodontal ligament of the cat canine were characterized by the presence of a cellular envelope which is the final form of the Henle sheath.
  • (2) Electron microscopic observations of the masseter nerve in the aged cats revealed a disruption of the myelin sheaths and a pronounced increase in collagen fibers in the endoneurium and perineurium.
  • (3) The authors propose three regular procedures with which they are experienced: repair with a large retromuscular nonabsorbable synthetic tulle prosthesis for extensive epigastric eventrations, fillup aponeuroplasty using the sheath of the rectus abdominis associated with a premuscular patch in case of diastasis or of multiple superimposed orifices and suture associated with a small retromuscular auxiliary patch to treat small incisional hernias.
  • (4) Extraction tools included flexible, telescoping sheaths advanced over the lead to dilate scar tissue and apply countertraction, deflection catheters, and wire basket snares.
  • (5) Thirteen soft tissue sarcomas with ultrastructural evidence of nerve sheath differentiation were investigated by immunohistochemistry.
  • (6) This cell population gives rise initially to oligodendrocytes and then to type-2 astrocytes, both of which apparently collaborate in sheathing axons in the CNS.
  • (7) Rabbit antirat T-cell serum (ALS(T)) reacted selectively with the surfaces of lymphocytes in the paracortex of lymph node and in the periarteriolar sheath of spleen, and with thymocytes.
  • (8) After properly fixing the vas deferens with a ring clamp, the surgeon pierces the scrotal skin, vas sheath, and vas deferens in the midline with a curved dissecting clamp held at a 45 degree angle from horizontal.
  • (9) We immunohistochemically examined the expression of Schwann cell-related markers, nerve growth factor (NGF) receptor, S-100 alpha- and beta-proteins, glial fibrillary acidic protein (GFAP), and galactocerebroside (gal C) in 5 malignant schwannomas, 21 benign peripheral nerve sheath tumors, and 4 apparently normal sural nerves.
  • (10) The transversalis fascia of the floor of the femoral canal turns down to form the medial wall of the venous compartment of the femoral sheath, and has the support of the curved edge of the lacunar ligament which effectively bars the femoral canal from entering the thigh.
  • (11) Unique domains of the retinal interphotoreceptor matrix (IPM), termed cone matrix sheaths, are composed largely of chondroitin 6-sulfate proteoglycan in most higher mammalian species.
  • (12) 2ME treatment caused partial solubilization of the sheaths (45% as determined by amino acid analysis), which could be further improved by combining 2ME with SDS.
  • (13) The 6.8F ultrasound balloon catheter was placed percutaneously in the right femoral artery through a 9F sheath.
  • (14) The isolated outer sheath was observed as a triple-layered, closed vesicle carrying a polygonal array by electron microscopy.
  • (15) These data show that the 515 nm absorbance change is not limited to small closed vesicles like grana, but in the presence of suitable electron donors single lamellae of bundle sheath chloroplasts can also be active.
  • (16) An outer sheath was isolated from Treponema phagedenis biotype Reiter by our previously developed method (Masuda, K., and Kawata, T. 1982.
  • (17) Seven tumours were predominantly of blue and spindle-cell, fascicular type, resembling malignant peripheral nerve sheath tumour and at times monophasic synovial sarcoma.
  • (18) Several additional groups of muscle cells of more limited mass and spatial distribution include the vulval muscles of hermaphrodites, the male sex muscles, the anal-intestinal muscles, and the gonadal sheath of the hermaphrodite.
  • (19) The notochord, which is composed of a stack of flat cells surrounded by a connective tissue sheath, elongates dramatically and begins straightening between stages 21 and 25.
  • (20) Under fluoroscopic control a lower polar calix was punctured with 18 G sheathed needle; a guide wire was introduced through the sheet.