The Spanish verb 'fundamentar' (meaning 'to establish firmly' or 'to base/ground something') comes from the Latin noun 'fundamentum' meaning 'foundation'. This Latin word was formed by combining 'fundus' (meaning 'base' or 'bottom') with the instrumental suffix '-mentum'. In Spanish, the verb was created by adding the verbal suffix '-ar' to this Latin base, transforming the noun into a verb meaning 'to establish a foundation for something' or 'to ground something firmly'.

Some related Spanish words that might be more familiar include 'fundamento' (foundation, basis), 'fondo' (bottom, background) and 'profundo' (deep). All these words share the Latin root 'fundus' meaning 'bottom' or 'base'. While 'fundamentar' refers to the act of establishing or grounding something, 'fundamento' is the foundation itself, and 'fondo' retained the original meaning of 'bottom'.

English speakers might recognize the connection to words like 'fundamental', 'foundation', and 'fund'. These all trace back to the same Latin root 'fundus'. While 'fundamental' refers to basic or essential principles (the foundation of something), 'foundation' is the base upon which something is built, and 'fund' originally referred to the bottom or base of something, eventually evolving to mean a base or stock of money. The connection between all these words lies in the concept of something basic or foundational.