'irregularly-produced' originates from the combination of 'irregularly' and 'produced', where 'irregularly' comes from 'irregular', meaning 'not regular', and 'produced' from 'produce', meaning 'to create or bring forth'.

'irregularly' changed from the Old French word 'irregulier', and 'produced' from the Latin word 'producere', eventually forming the modern English term 'irregularly-produced'.

Initially, 'irregularly' meant 'not following a regular pattern', and 'produced' meant 'created or made', which together evolved to describe something made inconsistently.