SECAI Core · phase 10 of 15 · noun

Homomorphic encryption

Method that allows computation of certain fields in a dataset without decrypting it.

The Explain card

Plain English
Homomorphic encryption lets you compute on data while it stays encrypted. The server does the math on ciphertext, returns an encrypted result, and only the data owner can decrypt the answer.
Example
A hospital sends encrypted patient records to a cloud-hosted risk model. The model scores each record without ever seeing plaintext, and the hospital decrypts the scores locally.
Why it matters
AI inference often means handing sensitive data to someone else's servers. Homomorphic encryption removes the need to trust the host with plaintext, though it is still slow and limited to certain operations.
Hook
Gloves on, box sealed: the work gets done without anyone touching the contents.

Word knowledge

How the word is built, where it came from, and what it sits beside in memory.

In a sentence

The fraud-detection server uses homomorphic encryption to score encrypted bank transactions while customer account values remain unreadable to the server.

Why these words
  • homomorphic Greek homos, same, and morphē, form describes a structure-preserving relationship between operations
  • encryption English en-, put into, and Greek kryptos, hidden names the cryptographic process modified by homomorphic
Where it came from
Origin
Coined in English from mathematical homomorphic and cryptographic encryption
Entered the language
late 20th century
What changed
Homomorphic first described structure-preserving mathematical mappings, then qualified encryption schemes whose operations preserve selected relationships.
How it is spelled
Pattern
The combining form homo- keeps its final o before the consonant m.
Pattern
The suffix -ic forms an adjective, and -ion forms a process noun.

Spelled like

  • homogeneous
  • homonym
  • isomorphic
  • decryption
Broken into chunks
  • homo
    • homogeneous
    • homonym
  • morph
    • morphology
    • isomorphic
  • crypt
    • cryptography
    • decrypt
  • tion
    • authentication
    • computation
What it sits beside

Same subject

  • ciphertext
  • public-key cryptography
  • secure multiparty computation
  • zero-knowledge proof

Same shape

  • homomorphism
  • isomorphic
  • polymorphic

cryptographic protections

  • homomorphic encryption
  • digital signatures
  • zero-knowledge proofs

mathematical structure words

  • homomorphic
  • isomorphic
  • polymorphic

Where it sits in the deck

Phase 10: Identity, Access, and Cryptographic Foundations

Before examining threats to systems, establish the foundational security primitives — identity, authentication, authorisation, and the cryptography underpinning them.

Neighbours in this phase