More about canicular
Canicular, “pertaining to Sirius, the Dog Star,” is equivalent to Latin Canīcula “Sirius” plus -āris, an adjective-forming suffix. Canīcula literally means “little dog” and is based on canis “dog,” plus the feminine diminutive suffix -cula (compare English -cle or -cule, as in molecule and particle). Canis survives today as French chien, Italian cane, and Portuguese cão, but Spanish can has declined in favor of perro, of unclear origin. A direct descendant of Canīcula is French canicule “heat wave,” which previously referred to the dog days of summer. This period of the year takes its name in both English and Romance languages from the appearance of Sirius in the northern sky, and the co-occurrence with hot weather gives dog days as well as French canicule their heated sense. Canicular was first recorded in English in the late 14th century.