The Spanish word 'pulso' (meaning 'pulse') comes from the Latin word 'pulsus', which meant 'beat' or 'pulse'. Going back further, 'pulsus' derived from the Latin verb 'pellere', meaning 'to push' or 'strike'. This etymology makes intuitive sense, as a pulse is essentially the rhythmic pushing or striking sensation we feel from our heartbeat through our blood vessels.

Several common Spanish words share this Latin root, including 'impulso' (impulse), 'propulsar' (to propel), and 'expulsar' (to expel). All these words maintain the core meaning of pushing or driving force that was present in the original Latin 'pellere'.

English speakers can easily connect 'pulso' to several familiar English words that share the same Latin ancestry. These include 'pulse', 'impulse', 'propulsion', and 'expel'. All these words retain some connection to the original meaning of pushing or driving force. The English word 'pulse' is particularly close in both meaning and form to the Spanish 'pulso', making it easy to remember.