The Spanish word 'despertador' (alarm clock) has its roots in the Latin verb 'expergere', meaning 'to awaken'. This evolved into the Latin past participle 'expertus' meaning 'awakened', which then developed into the Spanish adjective 'despierto' (awake). From 'despierto' came the verb 'despertar' (to wake up). Finally, by adding the agent suffix '-dor' (which indicates something or someone that performs an action) to 'despertar', we get 'despertador' - literally meaning 'that which wakes up', referring to an alarm clock.

Some simpler and more common Spanish words that share this etymology are 'despierto' (awake) and 'despertar' (to wake up). These are among the first words Spanish learners encounter when talking about daily routines and states of being. While 'despierto' describes the state of being awake, and 'despertar' is the action of waking up, 'despertador' is the instrument that helps perform this action.

While there aren't direct English cognates from this exact Latin root 'expergere', English speakers might find it interesting that the word 'expert' comes from the same Latin word 'expertus', though it developed along a different semantic path. While in Spanish the meaning stayed connected to 'awakening', in English it evolved to mean 'experienced' or 'knowledgeable' - perhaps from the idea of being 'awakened' to knowledge.