phase i is a noun meaning "a clinical trial on a few persons to determine the safety of a new drug or invasive medical device; for drugs, dosage or toxicity limits should be obtained". It carries one recorded sense.
a clinical trial on a few persons to determine the safety of a new drug or invasive medical device; for drugs, dosage or toxicity limits should be obtained
Definitions, synonyms and semantic relations for phase i come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.