Dinosaur names beginning with O include dinosaurs found by school children, dinosaurs that have been renamed countless times and dinosaurs who were accused of eating eggs! Although the list quite short It has some great dinosaurs on it.
We will take a look at all dinosaurs starting with 0 in this article of which there are over 20. If you want a full A to Z list you can check out the link here and below for out All Dinosaur names” A to Z dinosaur list.
Also, as with all of our A to Z dinosaur pages we have the table below to help you check other dinosaurs, we aim to cover them all but of course there are new dinosaurs almost every week so bear with us!
You can find other dinosaur names and information by following the links in the table above.
we have information on each of the dinosaur names beginning with O here, just a few details as the pages get long! We have also included links to more information where we have it so feel free to browse through and learn more if you have time.
Oksoko was an oviraptor family member from Mongolia. it would have lived 70 million years ago. it was discovered in 1974 though they were stolen by fossil poachers. In 2006 one was recovered ( its full name is rescued three headed Eagle)
It would have been just over a metre long
Oksoko Name Meaning: “Three Headed Eagle“
Ojoceratops was a horned face dinosaur ( ceratopsian) That lied in New Mexico 68 million years ago. There is some argument if it is a junior triceratops, or from a little earlier and maybe a junior Eotriceratops instead. I was named in 2010.
Ojoceratops Name Meaning: “Ojo Alamo horned Face”
Olorotitan was a hadrosaur ( duckbilled) dinosaur from 72 to 66 million years ago in Russia. it was discovered between 1999 and 2001 and named in 2003.
It is estimated to grow to over 26 feet long ( 8 Metres) and would have weighed over 7000 lbs ( 3400kg) It had a large hollow crest on its head
Olorotitan Name Meaning: “Titanic Swan”
Omeisaurus is a sauropod Dinosaur from the Middle Jurassic Period about 190 million years ago. In lived in what is now Sichuan, China. It was up to 20 metres long (66 feet) and was About 20, 000 lbs. ( 9800 Kg)
Omeisaurus Name Meaning: ” Omei Lizard”
Oohkotokia Was a member of the Ankylosaurus family. It lived in the Late Cretaceous period about 74 million years ago. It was named and classified in 2013 though it had been found 30 years before!
It was about 6 metres long ( 20 feet)
Oohkotokia Name Meaning: “Large Stone”
OpisthocoelicaudiaWas a sauropod Dinosaur from the Early Cretaceous Period about 70 million years ago. In lived in what is now Mongolia. It was up to 11-13 metres long ( 37 – 43 feet) and was found well preserved just missing its neck and skull.
It was discovered in 1965 but named in 1977 and would have weighed between 8000-25000 kg ( quite a range!)
Opisthocoelicaudia Name Meaning: ” strange wing”
Yimenosaurus was a feathered megaraptor from argentina. it lived about 76 to 70 million years ago and was a carnivore. it was discovered in 2008 and could be between 6-8.4 metres long ( 20-27 feet) and 1000-3000 lbs in weight.
Orkoraptor Name Meaning: “Orko thief”
Ornithodesmus is a small raptor family member ( dromaeosaur) from England. it lived about 125 million years ago and was discovered in 1887. it is only known from back bones so its appearance is not well known.
however its size is estimated to be about 1.8 meters ( 6 feet)
Ornithodesmus name meaning: “Bird Link”
Ornitholestes was small theropod dinosaur that lived in the USA In the Jurassic Period. It was thought to be over 2 metres ling and a carnivore. It was discovered / named in 1903.
Ornitholestes Name Meaning: “Bird robber”
Ornithomimus Name means Bird mimic and it looks like an ostrich! It was a fast runner possibly the fastest ever dinosaur (you can read more about this here).
it was found in 1889 and named by Marsh in 1890. It would have been up to 4 metres ling ( 12 feet) and weigh about 370 lb( 170 kg)
Ornithomimus Name Meaning: ” Bird Mimic”
OrnithopsisWas a Sauropod, and didn’t look much like a bird at all!! it was discovered in England in 1833 when it was considered to be an iguanodon fossil among other names. it is now thought to be a sauropod.
Ornithopsis Name Meaning: “Bird Like Ness”
Orodromeus was a bipedal dinosaur that lived in Montana, USA. It lived during the cretaceous period about 76 million years ago.
It wa herbivore dinosaur and about 2.5 metres.
Orodromeus Name Meaning: “Mountain runner”
Orthomerus was, possibly, a hadrosaur dinosaur from the netherlands. It was discovered in 1883 and lived during the late cretaceous about 66 million years ago.
Orthomerus Name Meaning: “Straight Femur”
.Was a herbivore dinosaur that is thought to be bipedal and have some adaptations for burrowing and running ( which is where its name comes from. It lived during the Early Cretaceous and was discovered /named in 2007
Oryctodromeus Name Meaning: “Digging Runner”
Osmakasaurus was an iguanodon dinosaur and therefore herbivorous. It was alive during the Early Cretaceous about 137 million years ago. it was originally thought to be a a camptosaurus when it was discovered in 1896 but was later re classified in 2011.
Osmakasaurus Name Meaning: “Canyon Lizard”
Ostafrikasaurus was a carnivorous theropod from Tanzania, Africa. It was alive during the late Jurassic 152-145 million years ago. It was discovered between 1909 and 1912.
it was estimated to be 28 feet long (over 8 metres) and likely weighed 2300 lbs (1200 kg) It was thought to be an early Spinosaurus family member.
Ostafrikasaurus Name Meaning: “East African Lizard”
Ostromia was a bird like dinosaur discovered in 1855 in Germany. it was first thought to be a pterodactyl but over 100 years later was reclassified as an Archeopteryx. In 2017 it was then changed to Ostromia.
Ostromia name Meaning: “For Ostrom”
Is now known as Naosaurus after being remained a few times in the 150 years since it was discovered. It would have lived 155-148 million years ago in the late Jurassic Period.
It was a small dinosaur at around 2 metres ( 6.6 feet long)
- Nanosaurus meaning: Small Lizard”
- Othnielia Name Meaning: “for Othniel”
Othnielosaurus turns out it is the same as nanosaurus as well! othniel Marsh didn’t have much luck with the dinosaurs named after him.
Othnielosaurus Name Meaning: ” Othniel’s Lizard”
Ouranosaurus was a herbivorous hadrosaur type of dinosaur that lived in What is now Niger and Cameroon. it was about 7-8.3 metres (23-27 feet) it was discovered between 1956 – 1970. It was named in 1976.
it was alive during the Early Cretaceous around weighed about 9,000 lbs( 4500 kg)
Ouranosaurus Name Meaning: “Brave Lizard”
Overosaurus is a South American Sauropod dinosaur. It lived during the early Cretaceous period. it was relatively small for a theropod at 10 metres ( 33 feet) long. Although discovered in 2002 it was
Overosaurus Name Meaning: “Overo Lizard”
Oviraptor was a feathered dinosaur from what is now mongolia. It was discovered in 1923. It was a small dinosaur, about 1.6 metres long ( 5.2 feet) and would have weighed up to 88 lbs ( 40 kg) it was both feathered and crested.
Oviraptor was first found next to what was thought then to be protoceratops eggs, and was assumed to be eating them. Hence the name. it turns out from further study it was actually their own eggs, and fossil were later found of them protecting eggs. Its name is really unfair!
Oviraptor Name Meaning: Egg Thief”
Was a iguanodon discovered in england in 1860. it was described by Richard Owen in 1874. He classified it as an actual iguanodon, bu tin 2009 it was reclassified as a separate species “owendon”
Owenodon name meaning “owens tooth”
Oxalaia was a Spinosaurus family member from Brazil that lived 100 – 93 million years ago. It was discovered in 1999 and named in 2011.
Although very large it is though to be smaller than the more famous spinosaurus. its length (though it is from very few fossils) is estimated to be 39 – 46 feet (12 to 14 metres) and its weight from 5000 – 7000 kg ( 11-16000 lbs.)
Oxalaia Name Meaning: “for Oxala”
Ozraptor is a carnivore theropod from Australia it was discovered in 1967 by 4 school children in Australia. At first it was thought to be a turtle fossil but was later found to be a carnivorous dinosaur from the late Jurassic about 169 million years ago.
it would have been about 2 metres long ( 6.6 feet).
Ozraptor Name Meaning: “Australian thief”
there you have all the dinosaur names beginning with O so far. As we mentioned there are about 20 or so dinosaur names beginning with O so far, and more are added each year. We will try to keep up~
Hi, I am Roy Ford a General Studies and English Teacher who has taught all over the world. What started as a fossil collection became a great way to teach, motivate and inspire students of all ages and all over the world about dinosaurs and from that and children’s love of dinosaurs came the site dinosaur facts for kids, a resource for all ages.