What's the difference between underlay and undersay?

Underlay

Definition:

(v. t.) To lay beneath; to put under.
(v. t.) To raise or support by something laid under; as, to underlay a cut, plate, or the like, for printing. See Underlay, n., 2.
(n.) To put a tap on (a shoe).
(v. i.) To incline from the vertical; to hade; -- said of a vein, fault, or lode.
(n.) The inclination of a vein, fault, or lode from the vertical; a hade; -- called also underlie.
(n.) A thickness of paper, pasteboard, or the like, placed under a cut, or stereotype plate, or under type, in the from, to bring it, or any part of it, to the proper height; also, something placed back of a part of the tympan, so as to secure the right impression.

Example Sentences:

(1) After about 3 weeks of culture, N-ethyl-N-nitrosourea-pretreated fetal rat brain cells showed focal proliferation of neural cells on an underlayer of flat, epithelioid cells.
(2) These in vitro findings probably account for the remarkable results obtained in infections which up to now had mortality rates of 30 to 60 per cent, depending on the patient's underlaying condition.
(3) The type I + III collagen underlayer is reorganized when grafted.
(4) On the other hand, the alpha blockers might interfere with the ionic mechanisms underlaying the 4-AP effect thus, masking the removal of the noradrenergic control, due to an alpha blockade.
(5) The stromal underlayer has the typical morphological structure: its cells are compactly packed in the form of a skein with stromal mechanocytes among them.
(6) It is suggested that the motoneuron excitability changes within the interspike interval underlay the relationship between the motoneuron firing rate and effectiveness of the excitatory afferent volley.
(7) We report the anatomical and functional results of 156 myringoplasty; 134 with onlay surgical technique and 22 with underlay technique.
(8) Repair of the tympanic membrane with an underlay connective tissue graft (fascia in 90%) was successful in 97% of the ears.
(9) The small, underlayer scales, which on the flagella are shown to be arranged in 24 rows, number about 350000; larger scales of more complex construction number about 20 000.
(10) On pathological basis (simple, purulent and cholestéatomatous otitis) they used the overlay or the underlay method.
(11) A circus movement with antegrad conduction through the AV node and retograde conduction through an accessory pathway was found as the underlaying mechanism of the tachycardia.
(12) Flat cytoplasmic extensions of squamous cells underlay most of the goblet cell basal pole which therefore had only a small area on the basal lamina.
(13) In arterial walls collagen type III was detected immediately underlaying the endothelial cell layer and in the tissue between tunica elastica interna and adventitia.
(14) After dividing the posterior anulus, the flaps are rotated anteriorly, a maneuver that provides ample exposure of the middle ear and greatly simplifies underlay fascia grafting.
(15) In double soft-agar culture, colony formations of cancer cells in the overlayer were stimulated or inhibited by the presence of various kinds of fibroblast in the underlayer.
(16) Charged £2,339 in September 2005 for supply and fitting of "magnolia cavalier cavalace velvet wool carpet with cloud and cumulus underlay".
(17) These facts do not contradict our previous suggestion that the lipid-protein interactions underlay the regulative action mechanism of the natural bioactive ligands.
(18) The colony-stimulating activity of unfractionated conditioned medium was equivalent to the activity of standard peripheral blood underlayers.
(19) Transmural infarction underlay each case of ruptured ventricular septum, while in ruptured papillary muscle 11 of 20 cases showed subendocardial infarction.
(20) This problem has been solved by the layering of an intermediate D2O solution under the BSA and subsequent removal of the BSA solution and the underlaying with D2O containing glutaraldehyde.