view without definition in information_schema.Views

Hello!

I realised that there are views in information_schema.Views without
definition but \d+ psql command shows the definition. Where does the
definition live, please?

SELECT    *
FROM    information_schema.Views
WHERE    Table_Schema NOT IN ('pg_catalog', 'information_schema')
    AND View_Definition IS NULL
LIMIT    10;

Regards
Hans Ginzel