Hastate: Arrowhead-shaped with basal lobes pointing outward from the midvein.*
Blue vervain (Verbena hastata), as the species name implies, has hastate leaves. The image above shows the plant flowering on the left and the hastate leaves on the right.
*Pell, S.K., Angell, B. (2016). A botanist’s vocabulary: 1300 terms explained and illustrated. Portland: Timber Press.