'upgrade' originates from the English word 'up' meaning 'higher' and 'grade' meaning 'level or step'. 'Focus' comes from the Latin word 'focus' meaning 'hearth or fireplace', metaphorically used for 'center of activity'.

'Upgrade' evolved from the combination of 'up' and 'grade' in the 19th century, while 'focus' retained its Latin form and meaning through Middle English.

Initially, 'focus' meant 'hearth', but over time it evolved to mean 'center of interest or activity'.