The Spanish word 'ceguedad' (meaning 'blindness') comes from combining the Spanish adjective 'ciego' ('blind') with the suffix '-dad', which forms abstract nouns indicating a quality or state. The word 'ciego' itself derives from the Latin word 'caecus', meaning 'blind'. This formation follows a common pattern in Spanish where adding '-dad' to an adjective creates a noun representing the state or condition of having that quality.

A simpler and more commonly used Spanish word in this word family is 'ciego' (meaning 'blind'). While 'ciego' is the adjective describing someone who cannot see, 'ceguedad' is the abstract noun referring to the condition or state of blindness. Another related word is 'cegar' (to blind), which is the verb form.

While there aren't any common modern English words directly derived from Latin 'caecus', there are some specialized terms like 'cecity' (medical term for blindness) and 'caecilian' (a type of blind amphibian). These words share the same Latin root 'caecus' with the Spanish 'ceguedad', though they're rarely used in everyday English.