What does a lanceleaf plant look like?
How tall does it grow?
Lance leaf is one of the common leaf shapes and does not refer to a specific plant. It means a narrow leaf that comes to a point like the end of a spear or lance. Some cultivars or hybrids have varying leaf shapes so "lanceleaf" is used as a descriptor to separate it from its cousins. One example is lance leaf coreopsis. Do you have the name of the plant in question?