'irregularly-supplied' originates from the combination of 'irregularly' and 'supplied', where 'irregularly' comes from Latin 'irregularis', meaning 'not regular', and 'supplied' is derived from Latin 'supplere', meaning 'to fill up'.

'irregularis' transformed into the Old French word 'irregulier', and eventually became the modern English word 'irregular'. 'Supplere' transformed into the Old French word 'souplir', and eventually became the modern English word 'supply'.

Initially, 'irregularly' meant 'not following a regular pattern', and 'supplied' meant 'provided'. Together, they evolved to mean 'not consistently provided'.