The Spanish word 'estornudo' (meaning 'sneeze') comes from the Spanish verb 'estornudar' ('to sneeze'), which developed from the Latin verb 'sternutare' meaning 'to sneeze repeatedly'. 'Sternutare' itself was derived from the Latin verb 'sternuere' meaning 'to sneeze'. The noun 'estornudo' was formed by adding the Spanish noun suffix '-o' to the verb stem.

The verb 'estornudar' is a closely related and commonly used Spanish word that you might encounter before learning 'estornudo'. When you hear someone say 'estornudar' (to sneeze), you can easily connect it to the noun 'estornudo' (a sneeze) since they share the same root.

While English 'sneeze' is not etymologically related to 'estornudo', there is an interesting connection to some scientific English words. The medical term 'sternutation' (meaning the act of sneezing) comes from the same Latin root 'sternutare'. You might also encounter this root in medical terms like 'sternutatory', referring to substances that cause sneezing.