Something immaterial that stands in the way and must be circumvented or surmounted:
— Lack of imagination is an obstacle to one's advancement.
— The poverty of a district is an obstacle to good education.

synonym: obstruction.

Roget 706: prevention, preclusion, obstruction, stoppage; embolus, embolism [Med.]; infarct [Med.]; interruption, interception, interclusion^†; hindrance, impedition^†; retardment^†, retardation; embarrassment, oppilation^†; coarctation^†, stricture, restriction; restraint etc. 751; inhibition etc. 761; blockade etc. (closure) 261.    interference, interposition; obtrusion; discouragement, discountenance.    impediment, let, obstacle, obstruction, knot, knag^†; check, hitch, contretemps, screw loose, grit in the oil.    bar, stile, barrier; [barrier to vehicles] turnstile, turnpike; gate, portcullis.    beaver dam; trocha^†; barricade etc. (defense) 717; wall, dead wall, sea wall, levee breakwater, groyne^†; bulkhead, block, buffer; stopper etc. 263; boom, dam, weir, burrock^†.    drawback, objection; stumbling-block, stumbling-stone; lion in the path, snag; snags and sawyers.    encumbrance, incumbrance^†; clog, skid, shoe, spoke; drag, drag chain, drag weight; stay, stop; preventive, prophylactic; load, burden, fardel^†, onus, millstone round one's neck, impedimenta; dead weight; lumber, pack; nightmare, Ephialtes^†, incubus, old man of the sea; remora.    difficulty etc. 704; insuperable etc. 471; obstacle; estoppel [Law]; ill wind; head wind etc. (opposition) 708; trammel, tether etc. (means of restraint) 752; hold back, counterpoise.    [person who hinders] damper, wet blanket, hinderer, marplot, killjoy; party pooper [Coll.]; party crasher, interloper.    trail of a red herring; opponent etc. 710.    ... show more

Dutch: opstructie, belemmering, obstakel, opstakel
Polish: ściana, próg, przeciwność, przeszkoda, bariera, przeciwieństwo, mur, zapora, tama, rafa

An obstruction that stands in the way (and must be removed or surmounted or circumvented).