The Spanish word 'abonado' comes from the verb 'abonar', which was formed by combining the Latin prefix 'ad-' (meaning 'toward') with the Latin word 'bonus' (meaning 'good') and the Spanish verb suffix '-ar'. The prefix 'ad-' changed to 'a-' before 'b' through a common sound change in Spanish. 'Abonar' literally meant 'to make good' or 'to improve.'

The form 'abonado' is the past participle of 'abonar', formed by adding the suffix '-ado'. It has developed specialized meanings including 'subscriber' (someone who has paid for or improved their status with a service) and 'fertilized' (soil that has been improved with nutrients).

Some related Spanish words include 'bueno' (good), which comes from the same Latin root 'bonus', and 'abono' (fertilizer), which is directly related to the verb 'abonar'. The connection between these words lies in the concept of making something better or improving its quality.

English words related to 'abonado' through the Latin root 'bonus' include 'bonus' itself (an extra good thing), 'bonify' (to make good), and 'bonanza' (a situation bringing prosperity). The word 'boon' (something helpful or beneficial) is also related. All these words share the core meaning of goodness or improvement that we see in 'abonado'.