Oberschlesien / Upper Silesia (1)

Objektkunst / object Art (16)

Obstanbau / fruit-growing (1)

Obstbau / pomiculture (1)

Obstzucht / fruit farm (4)

Okkultismus / occultism (3)

Ökologie / ecology (3)

Ökonomie / economy (56)

Ölbild / oil paint (12)

Olympiade / Olympiad (1)

Olympische Spiele / Olympic Games (1)

Ontologie / ontology (2)

Op-Art / optische Kunst (1)

op-art, optical art / optische Kunst (2)

Oper / opera (14)

Operette / operetta (2)

Operngeschichte / history of opera (10)

Optik / optics (9)

Orchester / orchestra (2)

Orchideen / orchids (1)

Orden / Medal / decoration (4)

Orden / order, religious order (40)

Ordenstracht / habit of a religious order (40)

Organische Chemie / organic chemistry (1)

Orgel / pipe organ (1)

Orgelbau / organbuilding (1)

Orgelgeschichte (1)

Orient / orient (32)

Orientalismus / orientalism (1)

Orientalistik / orientalism (10)

Orientteppich / oriental carpet, eastern carpet (1)

Original Acrylstich / original acryl engraving (1)

Original Aquarell / original watercolour painting (10)

Original Ölbild / original oil painting (11)

Original-Fotografie / Original-Photographie / original photograph (65)

Original-Grafik / Original-Graphik / original graphic (501)

Original-Heliografie / original-heliographic print (1)

Original-Heliogravüre / original-heliogravure (2)

Original-Holzschnitt / original woodcut (242)

Original-Holzstich / original wood engraving (27)

Original-Kupferstich / original copper engraving (58)

Original-Linolschnitt / original linocut (54)

Original-Lithografie / Original-Lithographie / original lithograph (247)

Original-Offset / original offset (17)

Original-Plastik / original sculpture (5)

Original-Radierung / original etching (428)

Original-Siebdruck, Serigrafie / original screenprint, silkscreen, serigraphy (39)

Original-Siebdruck, Serigrafie / original screenprint, silksreen, serigraphy (53)

Original-Zeichnung / original drawing (63)

Original-Zinkografie / original zincograph (2)

Originalfotografie / Originalphotographie / original photograph (2)

Originalgrafik / Originalgraphik / original graphic (97)

Originalholzschnitt / original woodcut (2)

Originalkupferstich / original copper engraving (9)

Originallinolschnitt / original linocut (3)

Originallithografie / Originallithographie / original lithograph (1)

Ornament, Ornamentik / fancywork / ornament (11)

Ornithologie, Vogelkunde / ornithology (10)

Ortskunde / Landeskunde / applied geography (146)

Osmanen / Ottomans (2)

Osmanisches Reich / Ottoman Empire (1)

ostasiatische Kunst / far eastern art (2)

Österreich / Austria (13)

österreichische Geschichte / austrian history (16)

österreichische Kunst / austrian art (15)

österreichische Literatur / austrian literature (29)

Osteuropa / eastern europe (9)

Ostpreußen / East Prussia (4)

Ostsee / Baltic sea (1)

Ozeanien / Oceania (4)