The word 'more dinosaur' implies greater size and quantity of prehistoric creatures. Its antonyms, however, suggest the opposite - absence, decrease, or extinction. 'Less dinosaur' would indicate a diminishment in the number of these creatures, while 'no dinosaur' would suggest a complete absence of them. 'Modern' or 'contemporary' would be an appropriate antonym as well, as these adjectives indicate a lack of connection to the past. 'Advanced' would also be a fitting antonym as it implies progress and evolution, which contrasts with the notion of dinosaur-era antiquity. In summary, the antonyms for 'more dinosaur' imply absence, reduction, modernity, and advancement.