diff --git a/src/Command.php b/src/Command.php
index 06b0783..582bd36 100644
--- a/src/Command.php
+++ b/src/Command.php
@@ -54,7 +54,7 @@ abstract class Command
      * Argument definitions.
      *
      * @var array<int,array<string,mixed>> Definitions keyed by position, each
-     * with optional "type", "required" and "default" keys
+     * with optional "name", "type", "required", "default" and "description" keys
      */
     protected array $argumentDefinitions = [];
     /**
@@ -388,12 +388,13 @@ protected function validateDefinitions(array $definitions, array $values, string
             $label = $translator->render('cli', $label, []);
         }
         foreach ($definitions as $key => $definition) {
+            $displayName = $this->definitionLabel($key, $definition);
             $value = $values[$key] ?? null;
             if ($value === null || $value === false) {
                 if (!empty($definition['required'])) {
                     $errors[] = $translator
-                        ? $translator->render('cli', 'validation.required', [$label, (string) $key])
-                        : $label . ' "' . $key . '" is required.';
+                        ? $translator->render('cli', 'validation.required', [$label, $displayName])
+                        : $label . ' "' . $displayName . '" is required.';
                 }
                 continue;
             }
@@ -409,8 +410,8 @@ protected function validateDefinitions(array $definitions, array $values, string
                     // A boolean (true) means the option was passed without a
                     // value, which is only valid for "flag" definitions
                     $errors[] = $translator
-                        ? $translator->render('cli', 'validation.type', [$label, (string) $key, $type])
-                        : $label . ' "' . $key . '" must be of type ' . $type . '.';
+                        ? $translator->render('cli', 'validation.type', [$label, $displayName, $type])
+                        : $label . ' "' . $displayName . '" must be of type ' . $type . '.';
                 }
                 continue;
             }
@@ -422,13 +423,32 @@ protected function validateDefinitions(array $definitions, array $values, string
             };
             if (!$valid) {
                 $errors[] = $translator
-                    ? $translator->render('cli', 'validation.type', [$label, (string) $key, $type])
-                    : $label . ' "' . $key . '" must be of type ' . $type . '.';
+                    ? $translator->render('cli', 'validation.type', [$label, $displayName, $type])
+                    : $label . ' "' . $displayName . '" must be of type ' . $type . '.';
             }
         }
         return $errors;
     }
 
+    /**
+     * Resolve the display label of a definition: its "name" when given,
+     * otherwise the array key (the argument position or option name).
+     *
+     * @param int|string $key The definition key
+     * @param array<string,mixed> $definition The definition
+     *
+     * @return string
+     */
+    #[Pure]
+    protected function definitionLabel(int | string $key, array $definition) : string
+    {
+        $name = $definition['name'] ?? null;
+        if (\is_string($name) && $name !== '') {
+            return $name;
+        }
+        return (string) $key;
+    }
+
     /**
      * Tells if the command is active.
      *
diff --git a/src/Commands/Help.php b/src/Commands/Help.php
index 8329dc9..efff803 100644
--- a/src/Commands/Help.php
+++ b/src/Commands/Help.php
@@ -103,7 +103,8 @@ protected function showArguments(Command $command) : void
         );
         $lastKey = \array_key_last($definitions);
         foreach ($definitions as $position => $definition) {
-            CLI::write('  ' . $position . '  ' . $this->describeDefinition($definition));
+            $label = $this->definitionLabel($position, $definition);
+            CLI::write('  ' . $label . '  ' . $this->describeDefinition($definition));
             $raw = $definition['description'] ?? null;
             $description = \is_string($raw) ? \trim($raw) : '';
             if ($description !== '') {
diff --git a/tests/ValidationTest.php b/tests/ValidationTest.php
index b3acbc4..3b73729 100644
--- a/tests/ValidationTest.php
+++ b/tests/ValidationTest.php
@@ -215,6 +215,63 @@ public function testPassedValuesAreNotOverriddenByDefaults() : void
         self::assertSame('5', $this->console->getOption('count'));
     }
 
+    public function testNamedArgumentIsUsedInErrorMessages() : void
+    {
+        $command = new ValidatedCommandMock($this->console);
+        $command->setArgumentDefinitions([
+            0 => ['name' => 'environment', 'type' => 'int', 'required' => true],
+        ]);
+        $this->console->addCommand($command);
+        $this->console->exec('validated');
+        self::assertStringContainsString('argument "environment" is required', Stderr::getContents());
+        self::assertStringNotContainsString('"0"', Stderr::getContents());
+    }
+
+    public function testNamedArgumentTypeErrorsUseTheName() : void
+    {
+        $command = new ValidatedCommandMock($this->console);
+        $command->setArgumentDefinitions([
+            0 => ['name' => 'retries', 'type' => 'int'],
+        ]);
+        $this->console->addCommand($command);
+        $this->console->exec('validated abc');
+        self::assertStringContainsString('argument "retries" must be of type int', Stderr::getContents());
+    }
+
+    public function testNamedOptionIsUsedInErrorMessages() : void
+    {
+        $command = new ValidatedCommandMock($this->console);
+        $command->setOptionDefinitions([
+            'count' => ['name' => 'attempts', 'type' => 'int', 'required' => true],
+        ]);
+        $this->console->addCommand($command);
+        $this->console->exec('validated 42');
+        self::assertStringContainsString('option "attempts" is required', Stderr::getContents());
+    }
+
+    public function testNamedArgumentInTranslatedErrors() : void
+    {
+        $console = new ConsoleMock(new Language('pt-br'));
+        $command = new ValidatedCommandMock($console);
+        $command->setArgumentDefinitions([
+            0 => ['name' => 'ambiente', 'type' => 'int', 'required' => true],
+        ]);
+        $console->addCommand($command);
+        $console->exec('validated');
+        self::assertStringContainsString('argumento "ambiente" é obrigatório.', Stderr::getContents());
+    }
+
+    public function testMissingNameFallsBackToTheKey() : void
+    {
+        $command = new ValidatedCommandMock($this->console);
+        $command->setArgumentDefinitions([
+            0 => ['type' => 'int', 'required' => true],
+        ]);
+        $this->console->addCommand($command);
+        $this->console->exec('validated');
+        self::assertStringContainsString('argument "0" is required', Stderr::getContents());
+    }
+
     public function testApplyDefaultsDirectlyFillsTheConsole() : void
     {
         $command = new ValidatedCommandMock($this->console);