diff --git a/share/man/man9/Makefile b/share/man/man9/Makefile
--- a/share/man/man9/Makefile
+++ b/share/man/man9/Makefile
@@ -1,6 +1,6 @@
 .include <src.opts.mk>
 
-PACKAGE=	kernel-man
+MANPACKAGE=	kernel-man
 
 MAN=	accept_filter.9 \
 	accf_data.9 \
diff --git a/share/mk/bsd.lib.mk b/share/mk/bsd.lib.mk
--- a/share/mk/bsd.lib.mk
+++ b/share/mk/bsd.lib.mk
@@ -82,6 +82,13 @@
 .else
 DEV_TAG_ARGS=	${TAG_ARGS}
 .endif
+
+# By default, put library manpages in the -dev subpackage, since they're not
+# usually interesting if the development files aren't installed.  This can be
+# overridden with an empty value to put them in the base package instead.
+# Note that bsd.man.mk ignores this setting if MANSPLITPKG is enabled.
+MANSUBPACKAGE?=	-dev
+
 .endif	# !defined(NO_ROOT)
 
 # ELF hardening knobs
diff --git a/share/mk/bsd.man.mk b/share/mk/bsd.man.mk
--- a/share/mk/bsd.man.mk
+++ b/share/mk/bsd.man.mk
@@ -61,6 +61,20 @@
 
 MANGROUPS?=	MAN
 
+# MAN_SUBPACKAGE is the subpackage manpages will be installed in.  When
+# MANSPLITPKG is enabled, this is ignored and the subpackage is forced
+# to be "-man", otherwise it defaults to empty so manpages go in the
+# base package.  This can be set to "-dev" for manpages that should go
+# in the -dev package.
+.if ${MK_MANSPLITPKG} == "no"
+MAN_SUBPACKAGE?=
+.else
+MAN_SUBPACKAGE=	-man
+.endif
+
+# The default man package, if not otherwise specified.
+MAN_PACKAGE=	${PACKAGE:Uutilities}
+
 # Backwards compatibility.
 MINSTALL?=	${MANINSTALL}
 
@@ -105,17 +119,13 @@
 ${__group}OWN?=		${MANOWN}
 ${__group}GRP?=		${MANGRP}
 ${__group}MODE?=	${MANMODE}
-${__group}PACKAGE?=	${PACKAGE:Uutilities}
+${__group}SUBPACKAGE?=	${MAN_SUBPACKAGE}
+${__group}PACKAGE?=	${MAN_PACKAGE}${${__group}SUBPACKAGE}
 
 # Tag processing is only done for NO_ROOT installs.
 .if defined(NO_ROOT)
-
 .if !defined(${__group}TAGS) || ! ${${__group}TAGS:Mpackage=*}
-.if ${MK_MANSPLITPKG} == "no" || ${${__group}PACKAGE:M*-man}
-${__group}TAGS+=	package=${${__group}PACKAGE}
-.else
-${__group}TAGS+=	package=${${__group}PACKAGE}-man
-.endif
+${__group}TAGS+=       package=${${__group}PACKAGE}
 .endif
 
 ${__group}TAG_ARGS=	-T ${${__group}TAGS:ts,:[*]}