Lewis & Short

ob-strŭo (opstr-), xi, ctum, 3, v. a., to build before or against; to build, block, or wall up; to stop up, barricade, render impassable (class.; cf. obsaepio, claudo, oppilo).

  1. I. Lit.: validum pro diruto obstruentes murum, Liv. 38, 29: frontem castrorum auxiliis, id. 5, 1.
    Esp., to build before so as to obstruct the light: obstructae fenestrae, Varr. R. R. 1, 4: FENESTRAS OPSTRVITO, Lex. Puteol. ap. Grut. 207, 2: luminibus alicujus, Cic. Dom. 44: jus luminum obstruendorum redimere, to purchase permission of a neighbor to build so as to obstruct his light, Inscr. Guarin. Comment. in Vet. Monument. 1, p. 64: portas, Caes. B. C. 1, 27: valvas aedis. Nep. Paus. 5: aditus, Cic. Brut. 4, 16: flumina, Caes. B. C. 3, 48: aquarum venas, Plin. 31, 3, 28, § 49: saxa, placed in the way, Ov. M. 3, 570: cujus aures morbus obstruxit, has stopped up, made deaf, Sen. Ben. 3, 17, 2: os obstruere, to close the mouth, to make silent, Vulg. Psa. 62, 12; id. Rom. 3, 19.
  2. II. Trop., to stop up, hinder, impede, obstruct: Catonis luminibus obstruxit haec posteriorum quasi exaggerata altius oratio, was a hinderance to, Cic. Brut. 17, 66: viri deus obstruit aures, stops, renders deaf, inexorable, Verg. A. 4, 440: perfugia improborum, shuts off, Cic. Sull. 28, 79: cognitionem difficultatibus, to impede, obstruct, id. Ac. 2, 3, 7: mentes, Tac. H. 3, 21.
        1. b. Intr., to be in the way: si officiens signis mons obstruet altus, Cic. Arat. 44.