From the Sanskrit to English dictionary:
Pratiprasava (प्रतिप्रसव).—
1) A counter-exception, an exception to an exception (wherein the general rule is shown to be applicable to cases falling under the exception); तृजकाभ्यां कर्तरि इत्यस्य प्रतिप्रसवोऽयं (tṛjakābhyāṃ kartari ityasya pratiprasavo'yaṃ) (yājakādibhiśca) Sk.
2) A contrary effect.
Derivable forms: pratiprasavaḥ (प्रतिप्रसवः).
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Pratiprasava (प्रतिप्रसव).—
1) (As opposed to anuprasava) tracing causes back to the origin as -a pot, a lump of mud, mud, clay, Pātañjala Yogadarśana.
2) Negation of (or exception to) a negation. The force of a प्रतिप्रसव (pratiprasava) is positive, limiting as it does the scope of a प्रतिषेध (pratiṣedha) or negation. Hence it is just the opposite of परिसंख्या (parisaṃkhyā) whose force is negative or exclusive since it limits the scope of a positive statement. प्रतिप्रसवोऽयं न परिसंख्या (pratiprasavo'yaṃ na parisaṃkhyā) ŚB. on MS.1.7.45.
Derivable forms: pratiprasavaḥ (प्रतिप्रसवः).
Pratiprasava is a Sanskrit compound consisting of the terms prati and prasava (प्रसव).
Reverend Jaganath Carrera, founder of the Yoga Life Society has a beautiful definition of pratiprasava from the Yoga Sutras of Patanjali. In it he states:
pratiprasava = return to its original state; resolving back into their cause, return to the original state, disassociation from the creation process, counter-order, inverse propagation, to resolve to a more elementary form, withdrawal from manifestation (See 2.10, 4.34) from prati = against, back + prasava = creation, beginning, pressing out, setting or being set in motion, impulse, course, rush, flight, stimulation, pursuit, begetting, procreation, generation, conception, delivery, birth, augmentation, from pra = before, forward + sava = pressing out, from su = generate, impel
-Reverend Jaganath Carrera.
Patanjali’s Words: Abhinivesah and Pratiprasava