seventh: the ordinal number marking the seventh item, day, month, or year in a sequence
This is simply the word "seventh," the ordinal formed from the Hebrew word for seven. Like the English "seventh," it answers the question "which one?" by placing something at position seven in a counted series: the seventh day, the seventh month, the seventh year, the seventh time around the walls of Jericho. There is only one thing the word means, and most of its uses are ordinary counting.
What makes "seventh" stand out in the Hebrew Bible is not a second meaning but where the count keeps landing. From the opening chapter of Genesis onward, the seventh slot in a series is the one God sets apart. God finishes creation in six days and rests on the seventh, blessing it and making it holy (Genesis 2:2 to 2:3); that pattern becomes the weekly sabbath, the day of rest commanded for the whole household (Exodus 20:10 to 20:11). The same rhythm scales up: the land itself keeps a sabbath in the seventh year, lying fallow while debts are released and slaves freed (Exodus 21:2; Leviticus 25:4), and the seventh month is the most festival-dense month of the calendar, holding the Festival of Trumpets, the Day of Atonement, and the Festival of Booths (Leviticus 23:24 to 23:34).
So when a reader meets "seventh" in these books, the word is doing two things at once: it is counting, and, very often, it is naming the appointed time of rest, release, and worship. The weight is carried by the contexts the number falls into, not by any extra sense hiding inside the word.