diary-float

diary-float is a compiled Lisp function in `diary-lib.el'.

(diary-float MONTH DAYNAME N &optional DAY MARK)

Diary entry for the Nth DAYNAME after/before MONTH DAY.
DAYNAME=0 means Sunday, DAYNAME=1 means Monday, and so on.
If N>0, use the Nth DAYNAME after MONTH DAY.
If N<0, use the Nth DAYNAME before MONTH DAY.
DAY defaults to 1 if N>0, and MONTH's last day otherwise.
MONTH can be a list of months, an integer, or `t' (meaning all months).
Optional MARK specifies a face or single-character string to use when
highlighting the day in the calendar.