diff --git a/src/schema/objects/files.yaml b/src/schema/objects/files.yaml
index 10cadf3bfa..acd9d84895 100644
--- a/src/schema/objects/files.yaml
+++ b/src/schema/objects/files.yaml
@@ -126,3 +126,8 @@ stimuli:
     A directory to store any stimulus files used during an experiment.
     See the [relevant section](SPEC_ROOT/modality-specific-files/task-events.md#stimuli-directory)
     for more information.
+descriptions:
+  display_name: Descriptions Definitions
+  file_type: regular
+  description: |
+    A TSV file describing labels found for the `desc` entity in a Derivatives dataset.
diff --git a/src/schema/rules/files/deriv/tables.yaml b/src/schema/rules/files/deriv/tables.yaml
new file mode 100644
index 0000000000..558390afd3
--- /dev/null
+++ b/src/schema/rules/files/deriv/tables.yaml
@@ -0,0 +1,7 @@
+---
+descriptions:
+  level: optional
+  stem: descriptions
+  extensions:
+    - .tsv
+    - .json
diff --git a/src/schema/rules/tabular_data/derivatives/common_derivatives.yaml b/src/schema/rules/tabular_data/derivatives/common_derivatives.yaml
index 3fef5e88fa..b101f314a1 100644
--- a/src/schema/rules/tabular_data/derivatives/common_derivatives.yaml
+++ b/src/schema/rules/tabular_data/derivatives/common_derivatives.yaml
@@ -10,3 +10,12 @@ SegmentationLookup:
     color: optional
     mapping: optional
   index_columns: [index]
+
+Descriptions:
+  selectors:
+    - path == "descriptions.tsv"
+  columns:
+    desc_id: required
+    description: required
+  index_columns: [desc_id, description]
+  additional_columns: allowed