diff --git a/registry/registry.go b/registry/registry.go
index 9679567ce..584028551 100644
--- a/registry/registry.go
+++ b/registry/registry.go
@@ -10,8 +10,8 @@ type Registrar interface {
 	Deregister(ctx context.Context, service *ServiceInstance) error
 }
 
-// Instancer is service instancer.
-type Instancer interface {
+// Discoverer is service discovery.
+type Discoverer interface {
 	// Service return the service instances in memory according to the service name.
 	Fetch(ctx context.Context, serviceName string) ([]*ServiceInstance, error)
 	// Watch creates a watcher according to the service name.
diff --git a/transport/grpc/client.go b/transport/grpc/client.go
index 53d661d37..3f3e3c6a8 100644
--- a/transport/grpc/client.go
+++ b/transport/grpc/client.go
@@ -39,9 +39,9 @@ func WithMiddleware(m middleware.Middleware) ClientOption {
 }
 
 // WithRegistry with client registry.
-func WithRegistry(in registry.Instancer) ClientOption {
+func WithRegistry(d registry.Discoverer) ClientOption {
 	return func(o *clientOptions) {
-		o.instancer = in
+		o.discoverer = d
 	}
 }
 
@@ -57,7 +57,7 @@ type clientOptions struct {
 	endpoint   string
 	timeout    time.Duration
 	middleware middleware.Middleware
-	instancer  registry.Instancer
+	discoverer registry.Discoverer
 	grpcOpts   []grpc.DialOption
 }
 
@@ -85,8 +85,8 @@ func dial(ctx context.Context, insecure bool, opts ...ClientOption) (*grpc.Clien
 	var grpcOpts = []grpc.DialOption{
 		grpc.WithUnaryInterceptor(unaryClientInterceptor(options.middleware, options.timeout)),
 	}
-	if options.instancer != nil {
-		grpcOpts = append(grpcOpts, grpc.WithResolvers(discovery.NewBuilder(options.instancer)))
+	if options.discoverer != nil {
+		grpcOpts = append(grpcOpts, grpc.WithResolvers(discovery.NewBuilder(options.discoverer)))
 	}
 	if insecure {
 		grpcOpts = append(grpcOpts, grpc.WithInsecure())
diff --git a/transport/grpc/resolver/discovery/builder.go b/transport/grpc/resolver/discovery/builder.go
index ec958b99a..aabe0e6d3 100644
--- a/transport/grpc/resolver/discovery/builder.go
+++ b/transport/grpc/resolver/discovery/builder.go
@@ -21,15 +21,15 @@ func WithLogger(logger log.Logger) Option {
 }
 
 type builder struct {
-	instancer registry.Instancer
-	logger    log.Logger
+	discoverer registry.Discoverer
+	logger     log.Logger
 }
 
 // NewBuilder creates a builder which is used to factory registry resolvers.
-func NewBuilder(in registry.Instancer, opts ...Option) resolver.Builder {
+func NewBuilder(d registry.Discoverer, opts ...Option) resolver.Builder {
 	b := &builder{
-		instancer: in,
-		logger:    log.DefaultLogger,
+		discoverer: d,
+		logger:     log.DefaultLogger,
 	}
 	for _, o := range opts {
 		o(b)
@@ -38,7 +38,7 @@ func NewBuilder(in registry.Instancer, opts ...Option) resolver.Builder {
 }
 
 func (d *builder) Build(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOptions) (resolver.Resolver, error) {
-	w, err := d.instancer.Watch(context.Background(), target.Endpoint)
+	w, err := d.discoverer.Watch(context.Background(), target.Endpoint)
 	if err != nil {
 		return nil, err
 	}