The name "pilosa" in the scientific name Bidens pilosa refers to the specific epithet of the plant. In the binomial nomenclature system used in taxonomy, the specific epithet follows the genus name and helps to further identify the species within that genus.
In this case, "pilosa" is the specific epithet of the plant, Bidens pilosa. It is used to distinguish this particular species within the genus Bidens.
Therefore, the name "pilosa" refers to the specific epithet of the black jack plant in the scientific name Bidens pilosa.
