diff --git a/.changeset/stale-ducks-warn.md b/.changeset/stale-ducks-warn.md
new file mode 100644
index 0000000..4e8fe6c
--- /dev/null
+++ b/.changeset/stale-ducks-warn.md
@@ -0,0 +1,5 @@
+---
+"@hydrofoil/vocabularies": patch
+---
+
+Missing terms in `knossos#`, `events#` and `query#`
diff --git a/src/vocabulary/events.ttl b/src/vocabulary/events.ttl
index 2f1416d..c3dd008 100644
--- a/src/vocabulary/events.ttl
+++ b/src/vocabulary/events.ttl
@@ -1,3 +1,4 @@
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
 PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
 prefix hyper-events: <https://hypermedia.app/events#>
@@ -14,8 +15,14 @@ hyper-events:eventSpec
 .
 
 hyper-events:objectSpec
-  a rdf:Property ;;
+  a rdf:Property ;
   rdfs:domain hyper-events:EventHandler ;
   rdfs:comment "Object of this property is a predicate-object pair, defining what object a handler applies to" ;
 .
 
+hyper-events:immediate
+  a rdf:Property ;
+  rdfs:domain hyper-events:EventHandler ;
+  rdfs:range xsd:boolean ;
+  rdfs:comment "Marks an event handler which should be executed synchronously" ;
+.
diff --git a/src/vocabulary/knossos.ttl b/src/vocabulary/knossos.ttl
index dd4f3df..d743ec1 100644
--- a/src/vocabulary/knossos.ttl
+++ b/src/vocabulary/knossos.ttl
@@ -1,3 +1,4 @@
+prefix foaf: <http://xmlns.com/foaf/0.1/>
 PREFIX hydra: <http://www.w3.org/ns/hydra/core#>
 prefix code: <https://code.described.at/>
 PREFIX schema: <http://schema.org/>
@@ -24,5 +25,17 @@ knossos:memberTemplate
   a rdf:Property ;
   rdfs:domain rdfs:Class ;
   rdfs:range hydra:IriTemplate ;
-  rdfs:comment "Defines an identifier template for newly created instances of given class. Used by knossos' default collection POST handler." ;
+  rdfs:comment
+    "Defines an identifier template for newly created instances of given class. Used by knossos' default collection POST handler." ;
+.
+
+knossos:System
+  a knossos:SystemAccount ;
+  rdfs:label "System" ;
+  rdfs:comment "A special knossos account name which by default has full control over a knossos API"
+.
+
+knossos:SystemAccount
+  a rdfs:Class ;
+  rdfs:subClassOf foaf:Agent ;
 .
diff --git a/src/vocabulary/query.ttl b/src/vocabulary/query.ttl
index 2e6abf5..f8f6579 100644
--- a/src/vocabulary/query.ttl
+++ b/src/vocabulary/query.ttl
@@ -11,3 +11,39 @@ hyper-query:filter
   schema:rangeIncludes code:EcmaScript ;
   rdfs:comment "Links to code which will be used to filter a hydra:Collection for example" ;
 .
+
+hyper-query:templateMappings
+  a rdf:Property ;
+  rdfs:comment
+    "(Blank) resource which was used to expand hydra:IriTemplate, resulting in the current resource's identifier" ;
+.
+
+hyper-query:preprocess
+  a rdf:Property ;
+  rdfs:domain rdfs:Class ;
+  schema:rangeIncludes code:EcmaScript ;
+  rdfs:comment
+    "Links to code which will be executed before a resource representation is passed to a request handler"
+.
+
+hyper-query:order
+  a rdf:Property ;
+  rdfs:comment
+    "Declares how a given resource (typically collection) is ordered. Its object must be an RDF List of hyper-query:OrderSpecification" ;
+.
+
+hyper-query:OrderSpecification
+  a rdfs:Class ;
+.
+
+hyper-query:path
+  a rdf:Property ;
+  rdfs:domain hyper-query:OrderSpecification ;
+  rdfs:comment "A valid SHACL Path which should be used to sort a collection" ;
+.
+
+hyper-query:direction
+  a rdf:Property ;
+  rdfs:domain hyper-query:OrderSpecification ;
+  rdfs:comment "Sort direction (`ldp:Ascending` or `ldp:Descending`)" ;
+.