What does aestival mean?
The definition of aestival
Æs”ti*val, a.
Etym: [L. aestivalis, aestivus, fr. aestas summer.]
Of or belonging to the summer; as, æstival diseases. [Spelt also estival.]
An English Dictionary
Of or belonging to the summer; as, æstival diseases. [Spelt also estival.]