Oberschlesien / Upper Silesia (2)

Objektkunst / object Art (14)

Obstanbau / fruit-growing (1)

Obstbau / pomiculture (1)

Obstzucht / fruit farm (5)

Okkultismus / occultism (3)

Ökologie / ecology (1)

Ökonomie / economy (58)

Ölbild / oil paint (2)

Olympiade / Olympiad (1)

Olympische Spiele / Olympic Games (1)

Op-Art / optische Kunst (2)

op-art, optical art / optische Kunst (1)

Oper / opera (10)

Operette / operetta (1)

Operngeschichte / history of opera (10)

Optik / optics (8)

Orchester / orchestra (2)

Orchideen / orchids (2)

Orden / Medal / decoration (4)

Orden / order, religious order (42)

Ordenstracht / habit of a religious order (42)

Organische Chemie / organic chemistry (1)

Orgel / pipe organ (1)

Orient / orient (43)

Orientalistik / orientalism (4)

Orientteppich / oriental carpet, eastern carpet (1)

Original Acrylstich / original acryl engraving (1)

Original Aquarell / original watercolour pinting (5)

Original Ölbild / original oil painting (10)

Original-Fotografie / Original-Photographie / original photograph (71)

Original-Grafik / Original-Graphik / original graphic (542)

Original-Heliografie / original-heliographic print (1)

Original-Heliogravüre / original-heliogravure (2)

Original-Holzschnitt / original woodcut (140)

Original-Holzstich / original wood engraving (20)

Original-Kupferstich / original copper engraving (51)

Original-Linolschnitt / original linocut (45)

Original-Lithografie / Original-Lithographie / original lithograph (192)

Original-Offset / original offset (9)

Original-Plastik / original sculpture (7)

Original-Radierung / original etching (385)

Original-Siebdruck, Serigrafie / original screenprint, silkscreen, serigraphy (40)

Original-Siebdruck, Serigrafie / original screenprint, silksreen, serigraphy (35)

Original-Zeichnung / original drawing (37)

Original-Zinkografie / original zincograph (2)

Originalfotografie / Originalphotographie / original photograph (3)

Originalgrafik / Originalgraphik / original graphic (55)

Originalholzschnitt / original woodcut (1)

Originalkupferstich / original copper engraving (11)

Originallinolschnitt / original linocut (3)

Originallithografie / Originallithographie / original lithograph (1)

Ornament, Ornamentik / fancywork / ornament (6)

Ornithologie, Vogelkunde / ornithology (10)

Ortskunde / Landeskunde / applied geography (213)

Osmanen / Ottomans (1)

Osmanisches Reich / Ottoman Empire (5)

ostasiatische Kunst / far eastern art (1)

Österreich / Austria (16)

österreichische Geschichte / austrian history (17)

österreichische Kunst / austrian art (8)

österreichische Literatur / austrian literature (32)

Osteuropa / eastern europe (6)

Ostpreußen / East Prussia (30)

Ostsee / Baltic sea (1)

Ozeanien / Oceania (2)