twin·ning 
(twĭnĭng)
(twĭnĭng)n.
1. The bearing of twins.
2. A pairing or union of two similar or identical objects.
3. Mineralogy The formation of twin crystals.
- psychosocially
- psychosomatic
- psychosomatically
- psychosurgeon
- psychosurgery
- psychosurgical
- psychotechnical
- psychotechnician
- psychotechnics
- psychotherapeutic
- psychotherapeutically
- psychotherapeutics
- psychotherapist
- psychotherapy
- psychotic
- psychotically
- psychotomimetic
- psychotomimetically
- psychotronic
- psychotropic
- psych-out
- psychro-
- psychrometer
- psychrophile
- psychrophilic