The Spanish word 'leído' is the past participle of the verb 'leer' (to read). It comes from the Latin word 'legere', which meant 'to read' or 'to choose'. The Latin 'legere' evolved into Spanish 'leer', and 'leído' is the past participle form used to indicate something that has been read or someone who is well-read.

Some related Spanish words that might be more familiar to beginners include the basic verb 'leer' (to read), 'lector' (reader), and 'lectura' (reading). All these words share the same Latin root 'legere' and maintain the core meaning related to reading.

Several English words are related to 'leído' through the Latin root 'legere'. These include 'legible' (able to be read), 'legend' (something to be read), 'lecture' (a reading or speech), and 'intelligent' (originally meaning 'choosing between'). While these words have evolved to have distinct meanings, they all trace back to the same Latin root meaning 'to read' or 'to choose'.