Pax is glossed as planting time and also connected with a drum, and Landa associates the month with a ceremony he names Pacum Chac, described in terms of war and of the war leaders. The two glosses do not sit together comfortably and the literature has read the month in both directions.
The planting reading raises the drift problem again. A month named for planting cannot have kept that seasonal fit across the centuries in a calendar without a leap day, so either the name records the season at the time the list was fixed, or it never referred to a season at all. Both positions are held, and the evidence does not decide between them.
A Maya date does not name a month and a number in the way a European one does. It names a day in the 260-day Tzolk'in, by number and sign, and a position in the 365-day Haab, by day and month, and the two together form the Calendar Round, which repeats only after 18,980 days, a little under fifty-two years. Within the Haab the days of a month are numbered from zero to nineteen, and the zero day is not called first but seated, the seating of the month, a usage the Classic inscriptions write with its own glyph.
The war reading rests on Landa alone and the planting reading on the etymology alone, which is a fair summary of the state of the evidence for most of the nineteen names. Where the atlas can state a structural fact about a month it does; where the meaning is contested it says so rather than choosing the more colourful option, since a month name confidently glossed on thin evidence is exactly the sort of claim that propagates.