The Spanish word 'listo', meaning 'ready' or 'clever', traces back to the Latin verb 'legere', which meant 'to read' or 'to choose'. This evolved into the Vulgar Latin past participle '*lexitus', meaning 'chosen' or 'read'. Over time, the meaning shifted from 'chosen' to 'ready' in Spanish, likely because something that has been chosen or selected is ready for use. The additional meaning of 'clever' developed because being mentally prepared or quick to understand demonstrates intelligence.

The Spanish word 'leer' (to read) is a cousin of 'listo', as they both derive from the Latin 'legere'. While 'leer' maintained the original meaning of reading, 'listo' developed along the path of being chosen or selected to eventually mean ready or clever.

Several English words share a connection with 'listo' through the Latin root 'legere'. These include 'lecture' (a reading or discourse), 'legend' (originally something to be read), and 'legible' (able to be read). While these English words maintained connections to reading, the Spanish 'listo' evolved to emphasize the selection aspect of the original Latin meaning, eventually coming to mean 'ready' or 'clever'.