'apical' originates from Latin, specifically the word 'apex', where 'apex' meant 'summit' or 'tip'.

'apical' changed from Medieval/Neo-Latin 'apicalis' (from Latin 'apex' + the adjectival suffix '-alis') and entered English from Late Latin/Medieval Latin as 'apical'.

Initially, it meant 'relating to an apex or tip', and over time this core meaning has been retained in modern usage as 'located at or toward the apex'.