+**18d** often refers to the numerical value of [Eighteen](/wiki/eighteen) or its ordinal form, the eighteenth. It can mark a specific point in a sequence or a duration within a [Time](/wiki/time) frame.
+## See also
+- [Calendar](/wiki/calendar)
+- [Numerology](/wiki/numerology)
+- [Dimension](/wiki/dimension)
... 1 more lines