back·cross 
(băkkrôs′, -krŏs′)
(băkkrôs′, -krŏs′)tr.v. back·crossed, back·cross·ing, back·cross·es
To cross (a hybrid) with one of its parents or with an individual genetically identical to one of its parents.
n.
1. The act of making such a cross.
2. An individual resulting from such a cross.
- infraction
- infractor
- infra dig
- infrahuman
- infrangibility
- infrangible
- infrangibly
- infraorder
- infrared
- infrared astronomy
- infrasonic
- infrasound
- infraspecific
- infrastructural
- infrastructure
- infrequence
- infrequency
- infrequent
- infrequently
- infringe
- infringement
- infringer
- infructescence
- in full cry
- in full swing