diff --git a/src/op/window-functions.js b/src/op/window-functions.js
index 833a9b47..b861538f 100644
--- a/src/op/window-functions.js
+++ b/src/op/window-functions.js
@@ -9,6 +9,11 @@ import NULL from '../util/null';
  * @return {void}
  */
 
+/**
+ * A storage object for the state of the window.
+ * @typedef {import('../engine/window/window-state').default} WindowState
+ */
+
 /**
  * Retrieve an output value from a window operator.
  * @callback WindowValue
@@ -16,6 +21,16 @@ import NULL from '../util/null';
  * @return {*} The output value.
  */
 
+/**
+ * Initialize an aggregate operator.
+ * @typedef {import('./aggregate-functions').AggregateInit} AggregateInit
+ */
+
+/**
+ * Retrive an output value from an aggregate operator.
+ * @typedef {import('./aggregate-functions').AggregateValue} AggregateValue
+ */
+
 /**
  * An operator instance for a window function.
  * @typedef {object} WindowOperator
@@ -30,6 +45,11 @@ import NULL from '../util/null';
  * @return {WindowOperator} The instantiated window operator.
  */
 
+/**
+ * Create a new aggregate operator instance.
+ * @typedef {import('./aggregate-functions').AggregateCreate} AggregateCreate
+ */
+
 /**
  * An operator definition for a window function.
  * @typedef {object} WindowDef
diff --git a/src/query/query.js b/src/query/query.js
index 9222afb5..c1b08a96 100644
--- a/src/query/query.js
+++ b/src/query/query.js
@@ -145,6 +145,11 @@ export default class Query extends Transformable {
   }
 }
 
+/**
+ * Abstract class representing a data table.
+ * @typedef {import('../table/table').default} Table
+ */
+
 /**
  * Serialized object representation of a query.
  * @typedef {object} QueryObject
diff --git a/src/query/verb.js b/src/query/verb.js
index 3fd167bd..e2321401 100644
--- a/src/query/verb.js
+++ b/src/query/verb.js
@@ -240,4 +240,9 @@ export const Verbs = {
   except:     createVerb('except', [
                 { name: 'tables', type: TableRefList }
               ])
-};
\ No newline at end of file
+};
+
+/**
+ * Abstract class representing a data table.
+ * @typedef {import('../table/table').default} Table
+ */
diff --git a/src/table/column-table.js b/src/table/column-table.js
index d78eaf81..afe1d4b5 100644
--- a/src/table/column-table.js
+++ b/src/table/column-table.js
@@ -79,7 +79,7 @@ export default class ColumnTable extends Table {
    * based on the values of the optional configuration argument. If a
    * setting is not specified, it is inherited from the current table.
    * @param {CreateOptions} [options] Creation options for the new table.
-   * @return {ColumnTable} A newly created table.
+   * @return {this} A newly created table.
    */
   create({ data, names, filter, groups, order }) {
     const f = filter !== undefined ? filter : this.mask();
@@ -146,9 +146,9 @@ export default class ColumnTable extends Table {
    * Get an array of values contained in a column. The resulting array
    * respects any table filter or orderby criteria.
    * @param {string} name The column name.
-   * @param {ArrayConstructor|import('./table').TypedArrayConstructor} [constructor=Array]
+   * @param {ArrayConstructor|TypedArrayConstructor} [constructor=Array]
    *  The array constructor for instantiating the output array.
-   * @return {import('./table').DataValue[]|import('./table).TypedArray} The array of column values.
+   * @return {DataValue[]|TypedArray} The array of column values.
    */
   array(name, constructor = Array) {
     const column = this.column(name);
@@ -162,7 +162,7 @@ export default class ColumnTable extends Table {
    * Get the value for the given column and row.
    * @param {string} name The column name.
    * @param {number} [row=0] The row index, defaults to zero if not specified.
-   * @return {import('./table').DataValue} The table value at (column, row).
+   * @return {DataValue} The table value at (column, row).
    */
   get(name, row = 0) {
     const column = this.column(name);
@@ -176,7 +176,7 @@ export default class ColumnTable extends Table {
    * function takes a row index as its single argument and returns the
    * corresponding column value.
    * @param {string} name The column name.
-   * @return {import('./table').ColumnGetter} The column getter function.
+   * @return {ColumnGetter} The column getter function.
    */
   getter(name) {
     const column = this.column(name);
@@ -240,7 +240,7 @@ export default class ColumnTable extends Table {
    * Instead, the backing data itself is filtered and ordered as needed.
    * @param {number[]} [indices] Ordered row indices to materialize.
    *  If unspecified, all rows passing the table filter are used.
-   * @return {ColumnTable} A reified table.
+   * @return {this} A reified table.
    */
   reify(indices) {
     const nrows = indices ? indices.length : this.numRows();
@@ -365,6 +365,36 @@ function objectBuilder(table) {
   return b;
 }
 
+/**
+ * Options for derived table creation.
+ * @typedef {import('./table').CreateOptions} CreateOptions
+ */
+
+/**
+ * A typed array constructor.
+ * @typedef {import('./table').TypedArrayConstructor} TypedArrayConstructor
+ */
+
+/**
+ * A typed array instance.
+ * @typedef {import('./table').TypedArray} TypedArray
+ */
+
+/**
+ * Table value.
+ * @typedef {import('./table').DataValue} DataValue
+ */
+
+/**
+ * Column value accessor.
+ * @typedef {import('./table').ColumnGetter} ColumnGetter
+ */
+
+/**
+ * Options for generating row objects.
+ * @typedef {import('./table').ObjectsOptions} ObjectsOptions
+ */
+
 /**
  * A table transformation.
  * @typedef {(table: ColumnTable) => ColumnTable} Transform
diff --git a/src/table/table.js b/src/table/table.js
index 88ef5ac8..737ab8f8 100644
--- a/src/table/table.js
+++ b/src/table/table.js
@@ -524,6 +524,11 @@ export default class Table extends Transformable {
  * @typedef {import('./bit-set').default} BitSet
  */
 
+/**
+ * Abstract class for custom aggregation operations.
+ * @typedef {import('../engine/reduce/reducer').default} Reducer
+ */
+
 /**
  * A table groupby specification.
  * @typedef {object} GroupBySpec
diff --git a/src/table/transformable.js b/src/table/transformable.js
index 488cbf70..b481573c 100644
--- a/src/table/transformable.js
+++ b/src/table/transformable.js
@@ -756,7 +756,7 @@ export default class Transformable {
 
 /**
  * A function defined over rows from two tables.
- * @typedef {(a?: Struct, b?: Struct, $?: Params) => any} TableFunc2
+ * @typedef {(a?: Struct, b?: Struct, $?: Params) => any} TableExprFunc2
  */
 
 /**