diestrous vs diestrual

diestrous and diestrual both are adjectives.

Word	Noun	Adjective	Verb	Adverb
diestrous	No	Yes	No	No
diestrual	No	Yes	No	No

As adjectives, diestrous and diestrual are synonyms defined as:

diestrous and diestrual: (of animals that have several estrous cycles in one breeding season) in a period of sexual inactivity

Other synonyms of diestrous include dioestrous, dioestrual.

diestrous (adjective)	diestrual (adjective)
(of animals that have several estrous cycles in one breeding season) in a period of sexual inactivity	(of animals that have several estrous cycles in one breeding season) in a period of sexual inactivity