### - d -

- DAY_TICKS : date_type.h
- DAYS_IN_LEAP_YEAR : date_type.h
- DAYS_IN_YEAR : date_type.h
- DEF_SNOWLINE_HEIGHT : tile_type.h
- DEF_START_YEAR : date_type.h
- DEFAULT_GROUP : group_type.h
- DEFAULT_RAINFOREST_TREE_STEPS : tree_cmd.cpp
- DEFAULT_TREE_STEPS : tree_cmd.cpp
- diagdir_names : dbg_helpers.cpp
- DisallowedPPPofTrackAtPCP : elrail_data.h
- DOWNARROW : widget.cpp
- DRAW_STRING_BUFFER : gfx_func.h