What does thumbprint mean?
A thumbprint is an impression made by pressing a thumb against a surface, usually after the thumb has been inked or coated. Because the skin of the fingertips has distinctive friction ridges, such impressions can reveal identifying patterns and have long been used for identification and recordkeeping. The word also figuratively describes a small mark or distinctive feature that makes a person, object, or creative work recognizable. In computing, a thumbprint is a compact cryptographic value, often derived from a digital certificate or public key, that helps users confirm that they have the correct key. Although thumbprint and fingerprint are sometimes used interchangeably in casual speech, a fingerprint is broader because it may come from any finger. The word is useful in contexts ranging from inked forms and biometric scanners to digital security, where its sense shifts from a physical impression to an identifying code.
A mark or impression made by pressing a thumb against a surface; also, by extension, a distinctive identifying sign or pattern.
"The witness left a thumbprint on the document."
In technical computing contexts, the term may denote a cryptographic digest used to identify a public key or certificate.
To make or leave a thumbprint on something.
"The applicant thumbprinted each page of the form."
This verb is uncommon outside contexts involving physical forms, ink, clay, or similar materials.
The standard plural is used for both individual impressions and the identifying features or digital values represented by the word.
"Several old thumbprints appeared on the dusty glass."
A thumbprint records tiny friction ridges on the skin, so even a partial impression can contain distinctive identifying information.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does thumbprint come from?
Thumbprint is an English compound formed from thumb and print. Thumb descends from Old English þūma, while print entered Middle English from Old French and ultimately relates to Latin terms for pressing or impressing. The compound developed in the sense of an impression made by a thumb before the word was extended to identifying marks and, much later, cryptographic digests.
How thumbprint is actually used
The noun is neutral in general use. In computing, it usually refers to a cryptographic digest rather than a biometric fingerprint. The verb is relatively uncommon and means to make or leave a thumbprint on something.
Easily confused with thumbprint
A thumbprint is specifically an impression made by a thumb, whereas a fingerprint may be made by any finger and often refers more broadly to biometric identification.