Ik is the Yucatec spelling; the K'iche' daykeepers of highland Guatemala call the same day Iq', and the Classic inscriptions write it with the T-shaped sign that scribes also used for wind and for breath in ordinary words. The T element appears carved through palace windows and worn as a pectoral, so the day sign and the architectural motif share an image, and both point at moving air.
In the central Mexican tonalpohualli the second position belongs to Ehecatl, wind, the aspect under which Quetzalcoatl was worshipped as the bringer of breath and of the storm that precedes rain. Maya Ik and Nahua Ehecatl agree exactly in meaning, one of the clearest matches in the twenty and a reminder that the 260-day count was shared property across Mesoamerica rather than the possession of a single culture.
Ik carries weight in the year as well as the trecena. It is one of the four Classic-period Year Bearers, the signs on which a 365-day Haab year is permitted to begin, together with Manik, Eb and Kaban; those four are spaced five apart in the twenty because 365 leaves a remainder of five when divided by twenty. The K'iche' communities that keep the count today use this same set under their own names, Iq', Kej, E and No'j, rather than the Kan, Muluc, Ix and Kawak that Landa recorded for Postclassic Yucatan.