Enhance once meant something entirely physical. When English borrowed it from Anglo-Norman enhauncer in the 13th century, to enhance a tower meant to make it taller, and to enhance a price meant to raise it higher. The word traces through Old French enhaucier back to Vulgar Latin *inaltiare, from Latin altus, which unusually meant both 'high' and 'deep.' The physical sense of lifting or raising dominated for two centuries before the figurative meaning — improving quality, value, or beauty — took hold in the 15th century. By the 17th century, nobody enhanced a wall any more; the word had migrated entirely into the abstract. The spelling also evolved: Middle English enhaunce lost its 'u' to become the modern enhance. Its Latin ancestor altus left a wide trail through English: altitude, altar, exalt, and even the musical term alto all share the same root.