Principal English Translation:
something thin, such as a delicate fabric (see Molina)
Alonso de Molina:
canauac. cosa delgada desta manera, lienzo, o manta delgada de algodon.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 12r. col. 2. Thanks to Joe Campbell for providing the transcription.
Attestations from sources in English:
canāhuac = thin
Michel Launey, An Introduction to Classical Nahuatl, translated and adapted by Christopher MacKay (Cambridge: Cambridge University Press, 2011), 110.
canaoac = thin (speaking of hair on cheeks) (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 10 -- The People, No. 14, Part 11, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1961), 111.
Attestations from sources in Spanish:
canahuac = "lienzos delgados...hechos por mujeres ricas" (citando el Códice Florentino, 1979, lib. II: 75) (p. 101)
Katarzyna Mikulska, "Te hago bandera... Signos de banderas y sus significados en la expresión gráfica nahua", en Los códices mesoamericanos: registros de religión, política y sociedad, Miguel Ángel Ruz Barrio y Juan José Batalla Rosado, coordinadores (Zinacantepec: El Colegio Mexiquense, 2016), 85–133.