diff --git a/frontend/src/tooltip/tooltip-model-test.ts b/frontend/src/tooltip/tooltip-model-test.ts
new file mode 100644
index 00000000..eceb3c0a
--- /dev/null
+++ b/frontend/src/tooltip/tooltip-model-test.ts
@@ -0,0 +1,60 @@
+import { enableI18n, event } from '../test-util';
+
+import { readit, rdfs, skos } from '../common-rdf/ns';
+import { FlatLdObject } from '../common-rdf/json';
+import Node from '../common-rdf/node';
+import FlatItem from '../common-adapters/flat-item-model';
+
+import toTooltip from './tooltip-model';
+
+function getDefaultAttributes(): FlatLdObject {
+    return {
+        '@id': readit('test'),
+        "@type": [rdfs.Class],
+        [skos.prefLabel]: [
+            { '@value': 'Content' },
+        ],
+        [skos.altLabel]: [
+            { '@value': 'alternativeLabel' }
+        ],
+        [skos.definition]: [
+            { '@value': 'This is a test definition' }
+        ],
+        [rdfs.comment]: [
+            { '@value': 'Also, I have a comment' }
+        ],
+    }
+}
+
+function getDefaultItem(): FlatItem {
+    return new FlatItem(new Node(getDefaultAttributes()));
+}
+
+describe('Tooltip model adapter', function () {
+    beforeAll(enableI18n);
+
+    beforeEach(function() {
+        this.item = getDefaultItem();
+    });
+
+    it('uses skos:definition if available', async function () {
+        const model = toTooltip(this.item);
+        await event(this.item, 'complete');
+        expect(model.get('text')).toEqual('This is a test definition');
+    });
+
+    it('uses rdfs:comment otherwise', async function() {
+        this.item.underlying.unset(skos.definition);
+        const model = toTooltip(this.item);
+        await event(this.item, 'complete');
+        expect(model.get('text')).toEqual('Also, I have a comment');
+    });
+
+    it('unsets the text when definition and comment are absent', async function() {
+        this.item.underlying.unset(skos.definition);
+        this.item.underlying.unset(rdfs.comment);
+        const model = toTooltip(this.item);
+        await event(this.item, 'complete');
+        expect(model.has('text')).toBe(false);
+    });
+});
diff --git a/frontend/src/tooltip/tooltip-model.ts b/frontend/src/tooltip/tooltip-model.ts
new file mode 100644
index 00000000..c06a6c04
--- /dev/null
+++ b/frontend/src/tooltip/tooltip-model.ts
@@ -0,0 +1,40 @@
+import * as i18next from 'i18next';
+
+import Model from '../core/model';
+import { rdfs, skos } from '../common-rdf/ns';
+import FlatItem from '../common-adapters/flat-item-model';
+
+/**
+ * Model adapter that lets you feed a `FlatItem` to a `TooltipView`.
+ *
+ * `TooltipView` expects a model with just a `text` attribute. The adapter
+ * extracts either the `skos:definition` or the `rdfs:comment`, depending on
+ * which is available, from the underlying model, and sets this as the `text`
+ * attribute. It takes the currently selected language into account.
+ *
+ * For optimum convenience, use the `toTooltip` helper function instead of
+ * instantiating the class directly.
+ */
+export class FlatAsTooltipAdapter extends Model {
+    constructor(underlying: FlatItem, options?: any) {
+        super(null, options);
+        underlying.when('classLabel', this.adapt, this);
+    }
+
+    adapt(underlying): void {
+        const cls = underlying.get('class');
+        const languageOption = { '@language': i18next.language };
+        const definition = cls.get(skos.definition, languageOption);
+        const comment = definition || cls.get(rdfs.comment, languageOption);
+        const text = definition && definition[0] || comment && comment[0];
+        this.set({text});
+    }
+}
+
+/**
+ * Helper function to wrap a `FlatItem` in a model with the expected attributes
+ * for a `TooltipView`.
+ */
+export default function toTooltip(model: FlatItem) {
+    return new FlatAsTooltipAdapter(model);
+}