supplementary (adj.)

• accessory
• accidental
• added
• additional
• adjunct
• adscititious
• adventitious
• ancillary
• another
• appurtenant
• attached
• auxiliary
• casual
• circumstantial
• collateral
• contingent
• contributory
• excess
• extra
• extraneous
• farther
• fortuitous
• fresh
• further
• incidental
• inessential
• more
• new
• nonessential
• other
• plus
• secondary
• spare
• subordinate
• subsidiary
• superfluous
• supernumerary
• supplemental
• supportive
• surplus
• ulterior
• unessential