diff --git a/Makefile b/Makefile
index 2baf0d6..4aacb99 100644
--- a/Makefile
+++ b/Makefile
@@ -77,7 +77,7 @@
 CPPFLAGS_valgrind = -O0
 OPENSSL_CFLAGS_valgrind = -DPURIFY
 LDFLAGS_valgrind =
-DEFINES_valgrind = _DEBUG DEBUG GRPC_TEST_SLOWDOWN_FACTOR=20
+DEFINES_valgrind = _DEBUG DEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=20
 
 VALID_CONFIG_tsan = 1
 REQUIRE_CUSTOM_LIBRARIES_tsan = 1
@@ -87,7 +87,7 @@
 LDXX_tsan = clang++
 CPPFLAGS_tsan = -O1 -fsanitize=thread -fno-omit-frame-pointer
 LDFLAGS_tsan = -fsanitize=thread
-DEFINES_tsan = NDEBUG GRPC_TEST_SLOWDOWN_FACTOR=10
+DEFINES_tsan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=10
 
 VALID_CONFIG_asan = 1
 REQUIRE_CUSTOM_LIBRARIES_asan = 1
@@ -97,7 +97,7 @@
 LDXX_asan = clang++
 CPPFLAGS_asan = -O1 -fsanitize=address -fno-omit-frame-pointer
 LDFLAGS_asan = -fsanitize=address
-DEFINES_asan = NDEBUG GRPC_TEST_SLOWDOWN_FACTOR=5
+DEFINES_asan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=5
 
 VALID_CONFIG_msan = 1
 REQUIRE_CUSTOM_LIBRARIES_msan = 1
@@ -108,7 +108,7 @@
 CPPFLAGS_msan = -O1 -fsanitize=memory -fsanitize-memory-track-origins -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1
 OPENSSL_CFLAGS_msan = -DPURIFY
 LDFLAGS_msan = -fsanitize=memory -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1
-DEFINES_msan = NDEBUG GRPC_TEST_SLOWDOWN_FACTOR=20
+DEFINES_msan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=20
 
 VALID_CONFIG_ubsan = 1
 REQUIRE_CUSTOM_LIBRARIES_ubsan = 1
@@ -119,7 +119,7 @@
 CPPFLAGS_ubsan = -O1 -fsanitize=undefined -fno-omit-frame-pointer
 OPENSSL_CFLAGS_ubsan = -DPURIFY
 LDFLAGS_ubsan = -fsanitize=undefined
-DEFINES_ubsan = NDEBUG GRPC_TEST_SLOWDOWN_FACTOR=10
+DEFINES_ubsan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=10
 
 VALID_CONFIG_gcov = 1
 CC_gcov = gcc