The Spanish verb 'largar' (meaning 'to release' or 'let go') comes from the Spanish adjective 'largo' ('long') combined with the verbal suffix '-ar'. The Spanish 'largo' itself derives from Latin 'largus', which meant 'abundant' or 'copious'. The semantic evolution from the Latin sense of abundance to the modern Spanish meaning of releasing or letting go can be understood through the concept of 'giving freely' or 'giving abundantly', which eventually specialized to mean 'releasing' or 'letting go' completely.

The most obvious related Spanish word is the common adjective 'largo' meaning 'long'. While 'largo' retained a more physical meaning related to length or duration, its derivative 'largar' developed a more abstract meaning of releasing or letting go. You might also encounter 'largarse' (the reflexive form) which means 'to leave' or 'to get out', as if 'letting oneself go' from a place.

While there aren't many common English words directly related to 'largar', we do have some words borrowed from the same Latin root 'largus'. These include 'large' (which preserved the original Latin sense of abundance and developed into meaning 'big' in size) and 'largesse' (meaning 'generosity' or 'the giving of money or gifts', which relates to the original Latin meaning of abundance).