onionskin

onionskin — noun

1. a very thin, strong, slightly see-through paper, light enough that you can read

1.nounC2
Definition

a very thin, strong, slightly see-through paper, light enough that you can read writing on the page beneath it, used in the past mainly for typewriter carbon copies and airmail letters.

Example

Esteban typed his airmail letters on onionskin so the postage would stay cheap.

typical context: airmail and lightweight correspondence

The lawyer kept a stack of onionskin in the drawer for carbon copies of every contract.

collocation: stack of onionskin / carbon copies

Common collocations
  • sheet of onionskin
  • onionskin copy
  • onionskin envelope
  • yellowing onionskin
Synonyms
  • tissue paper

    broader term; tissue paper is softer and used for wrapping, while onionskin is firm enough to write or type on.

  • airmail paper

    near-synonym for the specific lightweight letter-writing use case; airmail paper is sometimes pre-folded as an aerogram.

  • India paper

    another very thin printing paper; India paper is mostly used for Bibles and dictionaries, while onionskin was for office copies.

Antonyms
  • cardstock

    thick, stiff paper used for covers and cards — the opposite weight and feel.

  • cardboard

Grammar Patterns

uncountable noun

Usage Note

Uncountable; refers to the paper as a material, not individual sheets — say 'a sheet of onionskin' rather than 'an onionskin'. Almost always paired with historical contexts (typewriters, carbon copies, airmail) since lightweight digital alternatives have replaced it.

Common Mistakes

She bought three onionskins from the stationery shop.
She bought three sheets of onionskin from the stationery shop.
onionskin is uncountable; count it with 'sheet of'.
The onionskin paper is from an onion.
Onionskin is named after the dry outer layer of an onion because of how thin it looks.
the name is a comparison, not an ingredient.

Word family

Synonym discussion

Sense: noun/1

All four are very thin papers, but they live in different worlds. Onionskin is firm and slightly crinkly — strong enough to feed through a typewriter and hold ink without bleeding, which made it the standard for carbon copies and airmail. Tissue paper is much softer and floppier; you use it to wrap gifts or stuff into bags, not to write on. India paper is technically even thinner than onionskin and almost opaque despite its weight, which is why publishers chose it for Bibles and pocket dictionaries where many pages must fit in a small spine. Airmail paper overlaps with onionskin in purpose but is often sold as a pre-cut, pre-folded aerogram. Picture a 1960s office: typists banged out three onionskin carbons at once; nobody was writing on tissue paper.

onionskin ↗tissue paperIndia paperairmail paper

Common collocations

Nouns

  • onionskin copy
  • onionskin envelope
  • sheet of onionskin
  • onionskin paper

Phrases

  • a stack of onionskin
  • yellowing onionskin
  • a sheet of onionskin

Prepositions

  • onionskin between (pages)
  • written on onionskin
  • typed on onionskin

Etymology

Old EnglishEnglish

Named in the late 19th century after the dry, papery outer layer of an onion bulb, which it resembles in thinness and slight translucency. The compound 'onion' + 'skin' was an English coinage describing the paper directly by visual analogy rather than borrowing a Latin or French technical term — fitting for a product invented for everyday office use rather than fine printing.