The common name for Aconitum napellus, a plant with powerful neurotoxic compounds, is monkshood. The species is also called aconite, wolfsbane, and Venus’s chariot, but monkshood is the standard English common name used in botanical and general-reference sources.
Aconitum napellus is a perennial member of the buttercup family, Ranunculaceae, native to western and central Europe. Its tall flower spikes carry dark blue or violet blooms with a large, hood-like upper sepal. That helmet shape explains the name monkshood: the flower resembles the cowl or hood of a medieval monk.
The plant contains aconitine and related alkaloids, which can affect nerves, muscles, and the heart. Even handling the plant can be hazardous because some toxins may be absorbed through damaged skin. Historically, Aconitum preparations were associated with poisoned arrows and spears, while later herbal traditions used highly dangerous preparations medicinally.
“Wolfsbane” is a defensible alternate name, but it can also refer to other Aconitum species. That is why monkshood is the clearest answer for this exact species.