diff --git a/src/include/flmisc.h b/src/include/flmisc.h
index 067e3021..7188c9f4 100644
--- a/src/include/flmisc.h
+++ b/src/include/flmisc.h
@@ -72,7 +72,13 @@ private:
 
 #include <FL/Fl_Double_Window.H>
 #include <FL/Fl_Button.H>
+// Avoid 'nitems' macro collision between FreeBSD's sys/params.h and fltk's
+// FL/Fl_Check_Browser.H (http://www.fltk.org/str.php?L2984)
+#undef nitems
 #include <FL/Fl_Check_Browser.H>
+#define FLTK_nitems nitems
+#undef nitems
+// ^^^ Avoid 'nitems' macro collision
 #include "globals.h"
 
 class Mode_Browser : public Fl_Double_Window
diff --git a/src/include/logsupport.h b/src/include/logsupport.h
index 6edfd175..389ebcaa 100644
--- a/src/include/logsupport.h
+++ b/src/include/logsupport.h
@@ -9,7 +9,14 @@
 #include "qso_db.h"
 #include "adif_io.h"
 
+// Avoid 'nitems' macro collision in FreeBSD's sys/params.h
+// with fltk's FL/Fl_Check_Browser.H
+// ->nitems() is called by functions in this file
+
+#undef nitems
 #include "lgbook.h"
+#define FLTK_nitems nitems
+#undef nitems
 
 #ifdef __WOE32__
 #  define ADIF_SUFFIX "adi"
diff --git a/src/logbook/logsupport.cxx b/src/logbook/logsupport.cxx
index e3068ccd..d40ac3fe 100644
--- a/src/logbook/logsupport.cxx
+++ b/src/logbook/logsupport.cxx
@@ -146,7 +146,7 @@ void Export_CSV()
 	if (!p)
 		return;
 
-	for (int i = 0; i < chkExportBrowser->nitems(); i++) {
+	for (int i = 0; i < chkExportBrowser->FLTK_nitems(); i++) {
 		if (chkExportBrowser->checked(i + 1)) {
 			rec = qsodb.getRec(i);
 			rec->putField(EXPORT, "E");
@@ -172,7 +172,7 @@ void Export_TXT()
 	if (!p)
 		return;
 
-	for (int i = 0; i < chkExportBrowser->nitems(); i++) {
+	for (int i = 0; i < chkExportBrowser->FLTK_nitems(); i++) {
 		if (chkExportBrowser->checked(i + 1)) {
 			rec = qsodb.getRec(i);
 			rec->putField(EXPORT, "E");
@@ -203,7 +203,7 @@ void Export_ADIF()
 	if (!p)
 		return;
 
-	for (int i = 0; i < chkExportBrowser->nitems(); i++) {
+	for (int i = 0; i < chkExportBrowser->FLTK_nitems(); i++) {
 		if (chkExportBrowser->checked(i + 1)) {
 			rec = qsodb.getRec(i);
 			rec->putField(EXPORT, "E");
@@ -1436,7 +1436,7 @@ void WriteCabrillo()
 	if (!p)
 		return;
 
-	for (int i = 0; i < chkCabBrowser->nitems(); i++) {
+	for (int i = 0; i < chkCabBrowser->FLTK_nitems(); i++) {
 		if (chkCabBrowser->checked(i + 1)) {
 			rec = qsodb.getRec(i);
 			rec->putField(EXPORT, "E");