diff --git a/src/libexpr/nix_api_value.cc b/src/libexpr/nix_api_value.cc
index ba36fdc3c..4a4a56ac3 100644
--- a/src/libexpr/nix_api_value.cc
+++ b/src/libexpr/nix_api_value.cc
@@ -170,7 +170,7 @@ unsigned int nix_get_attrs_size(nix_c_context *context, const Value *value) {
   NIXC_CATCH_ERRS_RES(0);
 }
 
-double nix_get_double(nix_c_context *context, const Value *value) {
+double nix_get_float(nix_c_context *context, const Value *value) {
   if (context)
     context->last_err_code = NIX_OK;
   try {
@@ -299,7 +299,7 @@ nix_err nix_set_path_string(nix_c_context *context, Value *value,
   NIXC_CATCH_ERRS
 }
 
-nix_err nix_set_double(nix_c_context *context, Value *value, double d) {
+nix_err nix_set_float(nix_c_context *context, Value *value, double d) {
   if (context)
     context->last_err_code = NIX_OK;
   try {
diff --git a/src/libexpr/nix_api_value.h b/src/libexpr/nix_api_value.h
index 125189c94..6d1604a6f 100644
--- a/src/libexpr/nix_api_value.h
+++ b/src/libexpr/nix_api_value.h
@@ -151,7 +151,7 @@ unsigned int nix_get_attrs_size(nix_c_context *context, const Value *value);
  * @param[in] value Nix value to inspect
  * @return float contents, error info via context
  */
-double nix_get_double(nix_c_context *context, const Value *value);
+double nix_get_float(nix_c_context *context, const Value *value);
 /** @brief Get int value
  * @param[out] context Optional, stores error information
  * @param[in] value Nix value to inspect
@@ -236,13 +236,13 @@ nix_err nix_set_string(nix_c_context *context, Value *value, const char *str);
  */
 nix_err nix_set_path_string(nix_c_context *context, Value *value,
                             const char *str);
-/** @brief Set a double
+/** @brief Set a float
  * @param[out] context Optional, stores error information
  * @param[out] value Nix value to modify
- * @param[in] d the double
+ * @param[in] d the float, 64-bits
  * @return error code, NIX_OK on success.
  */
-nix_err nix_set_double(nix_c_context *context, Value *value, double d);
+nix_err nix_set_float(nix_c_context *context, Value *value, double d);
 /** @brief Set an int
  * @param[out] context Optional, stores error information
  * @param[out] value Nix value to modify