Development of male characteristics, such as facial hair, either as part of normal male maturation, or, pathologically, by people of either sex as a result of hormonal imbalance.
Source: PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 775 (https://doi.org/10.1515/pac-2015-1202)