Synonyms that are in the dictionary are marked in green. Synonyms that are not in the dictionary are marked in red.
Antonyms that are in the dictionary are marked in green. Antonyms that are not in the dictionary are marked in red.
That’s why they were considered "dark matter," Mougous says, since researchers knew that they were abundant but were unable to characterize their DNA.
Source: https://www.discovermagazine.com/health/diving-deep-into-the-mouths-microbial-dark-matter