Synonyms for On the side:

• adj.

  •additional (adjective)
  • supplementary,
  • new,
  • further,
  • spare,
  • more,
  • padding,
  • perker,
  • perk,
  • option,
  • affixed,
  • other,
  • newest,
  • added,
  • Appended,
  • over-and-above,
  • increased.
  •next (adjective)
  • consequent,
  • attached,
  • closest,
  • adjacent,
  • following,
  • neighboring,
  • abutting,
  • touching,
  • proximate,
  • nearest,
  • close,
  • adjoining,
  • later,
  • alongside,
  • Beside,
  • after,
  • succeeding,
  • meeting,
  • coming,
  • subsequent.
  •Other relevant words: (adjective)
  • next,
  • hard by,
  • side-by-side,
  • additional,
  • back-to-back,
  • coterminous,
  • ensuing.

• adv

  •Other relevant words: (adverb)
  • what's more,
  • more than,
  • along with,
  • besides,
  • not counting,
  • in conjunction with,
  • and all,
  • as well as,
  • conjointly,
  • other than,
  • over and above,
  • in other respects,
  • supplementary to,
  • whats more,
  • to boot,
  • on top of everything,
  • in distinction to,
  • together with,
  • with the exception of.

• adv.

  •all (adverb)
  • on the side.
  •besides (adverb)
  • exclusive of,
  • beyond,
  • aside from,
  • also,
  • likewise,
  • otherwise,
  • apart from,
  • additionally,
  • else,
  • plus,
  • moreover,
  • furthermore,
  • too,
  • added to,
  • extra,
  • yet,
  • secondly,
  • exceeding.
  •Other relevant words: (adverb)
  • in excess of,
  • further-more.

• n.

  •Other relevant words: (noun)
  • sidelong,
  • unofficially.

• Other synonyms:

  •Other relevant words (noun):
  • to the side,
  • farther,
  • nearby,
  • along the side of,
  • surreptitiously,
  • sly,
  • furtively,
  • quietly,
  • away,
  • along by,
  • among other things,
  • sneakily,
  • inter alia,
  • overplus,
  • slyly,
  • and so,
  • covertly,
  • similarly,
  • over,
  • altogether,
  • underhandedly,
  • again,
  • above,
  • abreast,
  • then,
  • on one side,
  • stealthily,
  • clandestinely,
  • and also,
  • by the side of,
  • past,
  • item,
  • therewith,
  • Slily,
  • on top of,
  • to one side,
  • on the sly,
  • in juxtaposition,
  • as well,
  • by,
  • in addition,
  • aside,
  • au reste,
  • lateral,
  • into the bargain,
  • by the same token,
  • all included.

Antonyms for On the side:

• adj.

  • additional
    necessary.
  • next
    previous, preceding, earlier.