thumbnail

Synonym discussion

Sense: noun/2

All three words refer to a reduced representation of something, but they differ in function and context. 'Thumbnail' specifically means a small version of an image or document page that shows its actual content at a reduced size — you can tell what the full file looks like. 'Preview' focuses on the act of seeing content before opening it; a preview may be larger or show a different subset of content (e.g. the first page of a document). 'Icon' is a small picture that represents a file, program, or function but does not display the actual content — a PDF icon looks the same whether the file is an invoice or a letter. 'Miniature' is a general word for a very small copy of something, often used in non-digital contexts (e.g. a miniature of a statue). For example: 'The folder showed thumbnails of each photo. I clicked a preview button to see a slide show. The icon for the album was a generic camera symbol.'

Common collocations

Etymology

Formed by combining 'thumb' (from Old English 'þūma', the short thick finger) with 'nail' (from Old English 'næġel', the hard layer at the fingertip). The figurative uses grew from a literal practice: in the 1850s, artists used 'thumbnail sketch' to mean a very small drawing — roughly the size of a thumbnail. By the early 1900s, 'thumbnail' alone came to mean anything brief or concise. The digital sense of a small preview image appeared in the 1930s and became widespread with the rise of graphical computer interfaces.