| Jasień | Jasień |
| Jasieńczyk | Jasieńczyk coat of arms |
| Jasiołda | Jasielda River |
| jaskier | buttercup |
| Jaskier lodnikowy | Ranunculus glacialis |
| Jaskier ostry | Ranunculus acris |
| Jaskier polny | Ranunculus arvensis |
| jaskinia | den |
| Jaskinia Blombos | Blombos Cave |
| Jaskinia Chauveta | Chauvet Cave |
| Jaskinia Krubera | Voronya Cave |
| Jaskinia Mamucia | Mammoth Cave National Park |
| Jaskinia Nowoafońska | New Athos Cave |
| Jaskinia Wiatrów | Cave of the Winds |
| Jaskinia Wielka Śnieżna | Jaskinia Wielka Śnieżna |
| Jaskinie Dziesięciu Tysięcy Buddów | Longmen Grottoes |
| Jaskinie Jenolan | Jenolan caves |
| Jaskinie Škocjańskie | Škocjan Caves |
| Jaskiniątka | Cave Kids |
| jaskra | glaucoma |
| jaskrawość subiektywna | luminosity |
| jaskrawy | violent |
| Jaskrowate | Ranunculaceae |
| Jaskrowce | Ranunculales |
| Jaskrowe | Ranunculidae |
| jaskółka | swallow |
| Jaskółka dymówka | Barn Swallow |
| Jaskółka rudawa | Red-rumped Swallow |
| Jaskółkowate | Swallow |
| Jasmila Žbanić | Jasmila Žbanić |
| Jasmin Wagner | Blümchen |
| Jasmonidy | Jasmonic acid |
| Jasna Góra | Jasna Góra Monastery |
| Jasna Polana | Yasnaya Polyana |
| jasne jak słońce | as clear as day |
| jasno | clearly |
| jasnobrązowy | flaxen |
| jasnota | deadnettle |
| Jasnota biała | Lamium album |
| Jasnota purpurowa | Red deadnettle |
| Jasnota różowa | Lamium amplexicaule |
| Jasnotowate | Lamiaceae |
| Jasnotowce | Lamiales |
| jasnowidz | seer |
| jasnowidzenie | clairvoyance |
| jasnowłosy | fair |
| Jasnoúă | Light |
| jasność | clarity |
| Jasność Eddingtona | Eddington limit |
| jasny | light |
| Jasnyj | Yasny |
| Jason Arnott | Jason Arnott |
| Jason Donovan | Jason Donovan |
| Jason Freese | Jason Freese |
| Jason Jackson | Stevie Wonder |
| Jason Lamy-Chappuis | Jason Lamy-Chappuis |
| Jason Lee | Jason Lee |
| Jason McCaslin | Jason McCaslin |
| Jason Momoa | Jason Momoa |
| Jason Newsted | Jason Newsted |
| Jason Patric | Jason Patric |
| Jason Reso | Jason Reso |
| Jason Statham | Jason Statham |
| Jason X | Jason X |
| Jason Čulina | Jason Čulina |
| Jasov | Jasov |
| Jasper Fforde | Jasper Fforde |
| Jasper Johns | Jasper Johns |
| jaspis | jasper |
| Jassir Al-Kahtani | Yasser Al-Qahtani |
| Jassy | Iaşi |
| Jastarnia | Jastarnia |
| Jastrowie | Jastrowie |
| jastrząb | hawk |
| Jastrząb gołębiarz | Goshawk |
| Jastrzębie-Zdrój | Jastrzebie Zdroj |
| Jastrzębiec pomarańczowy | Pilosella aurantiaca |
| Jastrzębiowate | Accipitridae |
| Jasynuwata | Yasynuvata |
| jaszczurka | lizard |
| Jaszczurka krokodylowata | Chinese Crocodile Lizard |
| Jaszczurka perłowa | Ocellated Lizard |
| Jaszczurka szklana | Slender glass lizard |
| Jaszczurka zielona | European green lizard |
| Jaszczurka żyworodna | Viviparous lizard |
| Jaszczurki | Lizard |
| Jaszczurki kolczaste | Cordylidae |
| Jaszczurki tarczowate | Gerrhosauridae |
| Jaszczurki właściwe | Lacertidae |
| Jaszczurnikowate | Synodontidae |
| jaszmak | yashmak |
| Jaszuny | Jašiūnai Manor |
| Jasło | Jasło |
| Jat | Yat |
| Jatagan | Yatagan |
| Jatrogenia | Iatrogenesis |
| jatrogenny | iatrogenic |
| Jaun | Jaun |
| Jaunde | Yaoundé |
| Java | Java |
| Java Development Kit | Java Development Kit |
| Java Media Framework | Java Media Framework |
| Java Message Service | Java Message Service |
| Java Modeling Language | Java Modeling Language |
| Java Native Interface | Java Native Interface |
| Java Runtime Environment | Java Runtime Environment |
| Java Secure Socket Extension | Java Secure Socket Extension |
| JavaBeans | JavaBean |
| JavaCC | JavaCC |
| JavaScript | JavaScript |
| JavaServer Faces | JavaServer Faces |
| JavaServer Pages | JavaServer Pages |
| Javerlhac-et-la-Chapelle-Saint-Rober | Javerlhac-et-la-Chapelle-Saint-Robert |
| Javi García | Francisco Javier García |
| Javi Navarro | Javier Navarro |
| Javier Aguirre | Javier Aguirre |
| Javier Balboa | Javier Balboa |
| Javier Bardem | Javier Bardem |
| Javier Cercas | Javier Cercas |
| Javier Clemente | Javier Clemente |
| Javier Echevarría Rodríguez | Javier Echevarría Rodríguez |
| Javier Gonzales | Javier Gonzales |
| Javier Lozano Barragán | Javier Lozano Barragán |
| Javier Martínez | Javi Martínez |
| Javier Mascherano | Javier Mascherano |
| Javier Portillo | Javier Portillo |
| Javier Pérez de Cuéllar | Javier Pérez de Cuéllar |
| Javier Saviola | Javier Saviola |
| Javier Solana | Javier Solana |
| Javier Urruticoechea | Javier Urruticoechea |
| Jawa | Java |
| Jawa Wschodnia | East Java |
| Jawa Zachodnia | West Java |
| Jawa Środkowa | Central Java |
| Jawaharlal Nehru | Jawaharlal Nehru |
| Jawajczycy | Javanese |
| Jawhar Mnari | Jawhar Mnari |
| Jawne | Yavne |
| Jawnuta | Jaunutis |
| jawny | plain |
| jawor | sycamore maple |
| Jaworniki | Javorníky |
| jaworznicki | jaworznian |
| Jaworzno | Jaworzno |
| Jaworzyna Śląska | Jaworzyna Śląska |
| Jaworów | Yavoriv |
| Jay Forrester | Jay Wright Forrester |
| Jay Hernández | Jay Hernandez |
| Jay Kay | Jason Kay |
| Jay Leno | Jay Leno |
| Jay Miner | Jay Miner |
| Jay Rockefeller | Jay Rockefeller |
| Jay-Z | Jay-Z |
| Jaya | Puncak Jaya |
| Jaya Bhaduri | Jaya Bachchan |
| Jayapura | Jayapura |
| Jayne Torvill | Jayne Torvill |
| jaz | weir |
| Jazata | Yazata |
| jazda | drive |
| Jazda drużynowa na czas | Team time trial |
| Jazda indywidualna | Single skating |
| jazda indywidualna na czas | individual time trial |
| jazda na dwa baty | double penetration |
| Jazernica | Jazernica |
| jazgarz | ruffe |
| jazgot | gibberish |
| Jazid I | Yazid I |
| Jazid ibn Muhammad | Yazid of Morocco |
| Jazmin Avendaño | Jazmin Avendaño |
| Jazon | Jason |
| Jazyczije | Iazychie |
| Jazydyzm | Yazidi |
| Jazygowie | Iazyges |
| jazz | jazz |
| Jazz Jackrabbit | Jazz Jackrabbit |
| Jazz-funk | Jazz-funk |
| Jazz-hop | Jazz rap |
| Jazz-rock | Jazz fusion |
| Jazłowiec | Yazlovets |
| Jaćwież | Yotvingia |
| Jaćwingowie | Yotvingians |
| jałmużna | alms |
| Jałomica | Ialomiţa River |
| jałowiec | juniper |
| Jałowiec chiński | Juniperus chinensis |
| Jałowiec pospolity | Juniperus communis |
| Jałta | Yalta |
| jałówka | heifer |
| Jaś | Johnny |
| Jaś i magiczna fasola | Jack and the Beanstalk |
| Jaś i Małgosia | Hansel and Gretel |
| jaśmin | jasmine |
| jaźwiec | badger |
| jaźń | ego |
| JBoss | JBoss application server |
| JDAM | Joint Direct Attack Munition |
| JDBC | Java Database Connectivity |
| JDM | Japanese domestic market |
| JE | HE |
