Concepts, descriptions & FSNs
A concept is the meaning; descriptions are its names. The FSN is the one name engineered to be unambiguous.
The answer in one paragraph
A concept is one clinical meaning with one permanent ID — 22298006 means
"myocardial infarction" forever, in every system. Descriptions are the human names
attached to that meaning: one Fully Specified Name (FSN) that is engineered to be
unambiguous, one preferred term per language, and any number of synonyms. The
key mental shift: the ID identifies the meaning, not a word. "Heart attack", "MI" and
"myocardial infarction" are three descriptions of one concept — search any of them, land
on the same identity.
Anatomy of the naming model
| Component | Example | Job |
|---|---|---|
| Concept ID | 22298006 | Permanent, meaningless machine identity |
| FSN | Myocardial infarction (disorder) | The unambiguous name — note the semantic tag |
| Preferred term | Myocardial infarction | What the UI shows by default |
| Synonyms | Heart attack, MI, Cardiac infarction | What humans type |
Why the FSN has that bracket
The parenthesised suffix — (disorder), (procedure), (body structure), (finding) —
is the semantic tag. It tells you which hierarchy the concept lives in and resolves
ambiguity that natural language can't: Hematoma (disorder) is a diagnosis;
Hematoma (morphologic abnormality) describes tissue. Same word, different meanings,
different concepts. When two concepts could share a name, the FSN never lets them.
Three rules that prevent real mistakes
- Never store the text, store the ID. Descriptions get edited and translated; the
concept ID never changes meaning. Systems exchange
22298006, humans see whatever their language's preferred term is. - Concepts can be inactivated, never deleted. Old records stay interpretable;
inactive concepts point to their replacements. Check the
activeflag. - Pick by FSN, display by preferred term. When coding, read the FSN (including its semantic tag) to confirm you have the right meaning; show users the friendly name.
How this feels in practice
Type "heart attack" into a terminology search (you'll do this live in Shabda): the
search matches a synonym, ranks concepts, and shows FSNs so you can pick the right
hierarchy. The record stores 22298006; a Tamil or Hindi interface can later show its
own preferred term without touching the stored data. That's language independence by
design.
Where to go next
Hierarchies & is-a relationships — how 360k concepts organise themselves so computers can reason with them.