diff --git a/fmt/format.h b/fmt/format.h
index 265c14b2..d4009910 100644
--- a/fmt/format.h
+++ b/fmt/format.h
@@ -1738,8 +1738,8 @@ struct AlignTypeSpec : AlignSpec {
   char type() const { return TYPE; }
 };
 
-// A full format specifier.
-class FormatSpec : public AlignSpec {
+// Format specifiers.
+class format_specs : public AlignSpec {
  private:
   template <typename Char>
   void set(fill_spec<Char> fill) {
@@ -1765,11 +1765,11 @@ class FormatSpec : public AlignSpec {
   int precision_;
   char type_;
 
-  FormatSpec(unsigned width = 0, char type = 0, wchar_t fill = ' ')
+  format_specs(unsigned width = 0, char type = 0, wchar_t fill = ' ')
   : AlignSpec(width, fill), flags_(0), precision_(-1), type_(type) {}
 
   template <typename... FormatSpecs>
-  explicit FormatSpec(FormatSpecs... specs)
+  explicit format_specs(FormatSpecs... specs)
     : AlignSpec(0, ' '), flags_(0), precision_(-1), type_(0){
     set(specs...);
   }
@@ -1855,7 +1855,7 @@ template <typename Char>
 class ArgFormatterBase {
  private:
   basic_writer<Char> &writer_;
-  FormatSpec &spec_;
+  format_specs &spec_;
 
   FMT_DISALLOW_COPY_AND_ASSIGN(ArgFormatterBase);
 
@@ -1883,7 +1883,7 @@ class ArgFormatterBase {
 
  protected:
   basic_writer<Char> &writer() { return writer_; }
-  FormatSpec &spec() { return spec_; }
+  format_specs &spec() { return spec_; }
 
   void write(bool value) {
     writer_.write_str(StringRef(value ? "true" : "false"), spec_);
@@ -1897,7 +1897,7 @@ class ArgFormatterBase {
  public:
   typedef Char char_type;
 
-  ArgFormatterBase(basic_writer<Char> &w, FormatSpec &s)
+  ArgFormatterBase(basic_writer<Char> &w, format_specs &s)
   : writer_(w), spec_(s) {}
 
   void operator()(monostate) {
@@ -2045,7 +2045,7 @@ class ArgFormatter : public internal::ArgFormatterBase<Char> {
     \endrst
    */
   ArgFormatter(basic_writer<Char> &writer, basic_format_context<Char> &ctx,
-               FormatSpec &spec)
+               format_specs &spec)
   : internal::ArgFormatterBase<Char>(writer, spec), ctx_(ctx) {}
 
   using internal::ArgFormatterBase<Char>::operator();
@@ -2255,14 +2255,14 @@ class basic_writer {
 
   // Formats a floating-point number (double or long double).
   template <typename T>
-  void write_double(T value, const FormatSpec &spec);
+  void write_double(T value, const format_specs &spec);
 
   // Writes a formatted string.
   template <typename StrChar>
   CharPtr write_str(const StrChar *s, std::size_t size, const AlignSpec &spec);
 
   template <typename StrChar>
-  void write_str(BasicStringRef<StrChar> str, const FormatSpec &spec);
+  void write_str(BasicStringRef<StrChar> str, const format_specs &spec);
 
   // This following methods are private to disallow writing wide characters
   // and strings to a char buffer. If you want to print a wide string as a
@@ -2382,11 +2382,11 @@ class basic_writer {
   template <typename T, typename... FormatSpecs>
   typename std::enable_if<std::is_integral<T>::value, void>::type
       write(T value, FormatSpecs... specs) {
-    write_int(value, FormatSpec(specs...));
+    write_int(value, format_specs(specs...));
   }
 
   void write(double value) {
-    write_double(value, FormatSpec());
+    write_double(value, format_specs());
   }
 
   /**
@@ -2396,7 +2396,7 @@ class basic_writer {
     \endrst
    */
   void write(long double value) {
-    write_double(value, FormatSpec());
+    write_double(value, format_specs());
   }
 
   /**
@@ -2427,7 +2427,7 @@ class basic_writer {
 
   template <typename... FormatSpecs>
   void write(BasicStringRef<Char> str, FormatSpecs... specs) {
-    write_str(str, FormatSpec(specs...));
+    write_str(str, format_specs(specs...));
   }
 
   void clear() FMT_NOEXCEPT { buffer_.clear(); }
@@ -2461,7 +2461,7 @@ typename basic_writer<Char>::CharPtr basic_writer<Char>::write_str(
 template <typename Char>
 template <typename StrChar>
 void basic_writer<Char>::write_str(
-    BasicStringRef<StrChar> s, const FormatSpec &spec) {
+    BasicStringRef<StrChar> s, const format_specs &spec) {
   // Check if StrChar is convertible to Char.
   internal::CharTraits<Char>::convert(StrChar());
   if (spec.type_ && spec.type_ != 's')
@@ -2649,7 +2649,7 @@ void basic_writer<Char>::write_int(T value, Spec spec) {
 
 template <typename Char>
 template <typename T>
-void basic_writer<Char>::write_double(T value, const FormatSpec &spec) {
+void basic_writer<Char>::write_double(T value, const format_specs &spec) {
   // Check type.
   char type = spec.type();
   bool upper = false;
@@ -3366,7 +3366,7 @@ template <typename ArgFormatter, typename Char, typename Context>
 void do_format_arg(basic_writer<Char> &writer, basic_format_arg<Context> arg,
                    Context &ctx) {
   const Char *&s = ctx.ptr();
-  FormatSpec spec;
+  format_specs spec;
   if (*s == ':') {
     if (visit(internal::CustomFormatter<Char, Context>(writer, ctx), arg))
       return;
diff --git a/fmt/printf.h b/fmt/printf.h
index 0219ef8e..c2694e43 100644
--- a/fmt/printf.h
+++ b/fmt/printf.h
@@ -170,12 +170,12 @@ class CharConverter {
 // left alignment if it is negative.
 class PrintfWidthHandler {
  private:
-  FormatSpec &spec_;
+  format_specs &spec_;
 
   FMT_DISALLOW_COPY_AND_ASSIGN(PrintfWidthHandler);
 
  public:
-  explicit PrintfWidthHandler(FormatSpec &spec) : spec_(spec) {}
+  explicit PrintfWidthHandler(format_specs &spec) : spec_(spec) {}
 
   template <typename T>
   typename std::enable_if<std::is_integral<T>::value, unsigned>::type
@@ -224,14 +224,14 @@ class PrintfArgFormatter : public internal::ArgFormatterBase<Char> {
     specifier information for standard argument types.
     \endrst
    */
-  PrintfArgFormatter(basic_writer<Char> &writer, FormatSpec &spec)
+  PrintfArgFormatter(basic_writer<Char> &writer, format_specs &spec)
   : internal::ArgFormatterBase<Char>(writer, spec) {}
 
   using Base::operator();
 
   /** Formats an argument of type ``bool``. */
   void operator()(bool value) {
-    FormatSpec &fmt_spec = this->spec();
+    format_specs &fmt_spec = this->spec();
     if (fmt_spec.type_ != 's')
       return (*this)(value ? 1 : 0);
     fmt_spec.type_ = 0;
@@ -240,7 +240,7 @@ class PrintfArgFormatter : public internal::ArgFormatterBase<Char> {
 
   /** Formats a character. */
   void operator()(Char value) {
-    const FormatSpec &fmt_spec = this->spec();
+    const format_specs &fmt_spec = this->spec();
     basic_writer<Char> &w = this->writer();
     if (fmt_spec.type_ && fmt_spec.type_ != 'c')
       w.write_int(value, fmt_spec);
@@ -302,7 +302,7 @@ class printf_context :
   typedef internal::format_context_base<Char, printf_context> Base;
   typedef typename Base::format_arg format_arg;
 
-  void parse_flags(FormatSpec &spec, const Char *&s);
+  void parse_flags(format_specs &spec, const Char *&s);
 
   // Returns the argument with specified index or, if arg_index is equal
   // to the maximum unsigned value, the next argument.
@@ -311,7 +311,7 @@ class printf_context :
       unsigned arg_index = (std::numeric_limits<unsigned>::max)());
 
   // Parses argument index, flags and width and returns the argument index.
-  unsigned parse_header(const Char *&s, FormatSpec &spec);
+  unsigned parse_header(const Char *&s, format_specs &spec);
 
  public:
   /**
@@ -330,7 +330,7 @@ class printf_context :
 };
 
 template <typename Char, typename AF>
-void printf_context<Char, AF>::parse_flags(FormatSpec &spec, const Char *&s) {
+void printf_context<Char, AF>::parse_flags(format_specs &spec, const Char *&s) {
   for (;;) {
     switch (*s++) {
       case '-':
@@ -369,7 +369,7 @@ typename printf_context<Char, AF>::format_arg printf_context<Char, AF>::get_arg(
 
 template <typename Char, typename AF>
 unsigned printf_context<Char, AF>::parse_header(
-  const Char *&s, FormatSpec &spec) {
+  const Char *&s, format_specs &spec) {
   unsigned arg_index = std::numeric_limits<unsigned>::max();
   Char c = *s;
   if (c >= '0' && c <= '9') {
@@ -415,7 +415,7 @@ void printf_context<Char, AF>::format(basic_writer<Char> &writer) {
     }
     internal::write(writer, start, s - 1);
 
-    FormatSpec spec;
+    format_specs spec;
     spec.align_ = ALIGN_RIGHT;
 
     // Parse argument index, flags and width.
diff --git a/test/custom-formatter-test.cc b/test/custom-formatter-test.cc
index e1ece844..8c646211 100644
--- a/test/custom-formatter-test.cc
+++ b/test/custom-formatter-test.cc
@@ -17,7 +17,7 @@ using fmt::PrintfArgFormatter;
 class CustomArgFormatter : public fmt::ArgFormatter<char> {
  public:
   CustomArgFormatter(fmt::writer &w, fmt::basic_format_context<char> &ctx,
-                     fmt::FormatSpec &s)
+                     fmt::format_specs &s)
   : fmt::ArgFormatter<char>(w, ctx, s) {}
 
   using fmt::ArgFormatter<char>::operator();
@@ -33,7 +33,7 @@ class CustomArgFormatter : public fmt::ArgFormatter<char> {
 // rounded to 0.
 class CustomPrintfArgFormatter : public PrintfArgFormatter<char> {
  public:
-  CustomPrintfArgFormatter(fmt::basic_writer<char> &w, fmt::FormatSpec &spec)
+  CustomPrintfArgFormatter(fmt::basic_writer<char> &w, fmt::format_specs &spec)
   : PrintfArgFormatter<char>(w, spec) {}
 
   using PrintfArgFormatter<char>::operator();
diff --git a/test/format-test.cc b/test/format-test.cc
index 656551cb..db9faef0 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -1644,7 +1644,7 @@ class MockArgFormatter : public fmt::internal::ArgFormatterBase<char> {
   typedef fmt::internal::ArgFormatterBase<char> Base;
 
   MockArgFormatter(fmt::writer &w, fmt::format_context &ctx,
-                   fmt::FormatSpec &s)
+                   fmt::format_specs &s)
     : fmt::internal::ArgFormatterBase<char>(w, s) {
     EXPECT_CALL(*this, call(42));
   }
diff --git a/test/ostream-test.cc b/test/ostream-test.cc
index b5c46a61..c2498e90 100644
--- a/test/ostream-test.cc
+++ b/test/ostream-test.cc
@@ -60,14 +60,14 @@ TEST(OStreamTest, Enum) {
 
 struct TestArgFormatter : fmt::ArgFormatter<char> {
   TestArgFormatter(fmt::writer &w, fmt::format_context &ctx,
-                   fmt::FormatSpec &s)
+                   fmt::format_specs &s)
     : fmt::ArgFormatter<char>(w, ctx, s) {}
 };
 
 TEST(OStreamTest, CustomArg) {
   fmt::MemoryWriter writer;
   fmt::format_context ctx("}", fmt::format_args());
-  fmt::FormatSpec spec;
+  fmt::format_specs spec;
   TestArgFormatter af(writer, ctx, spec);
   visit(af, fmt::internal::make_arg<fmt::format_context>(TestEnum()));
   EXPECT_EQ("TestEnum", writer.str());