'alkaloidic' originates from 'alkaloid' with the suffix '-ic', where 'alkaloid' refers to a class of naturally occurring organic compounds, and '-ic' forms adjectives meaning 'of or pertaining to'.

'alkaloidic' was formed in English by adding the suffix '-ic' to 'alkaloid', following the pattern of forming adjectives from nouns.

Initially, it meant 'pertaining to alkaloids', and this meaning has remained unchanged in modern usage.