There is left uncovertebral hypertrophy at c5-c6 causing mild to moderate left foraminal stenosis. what does the mean ?

Spinal stenosis: This is a condition resulting from degenerative changes in the spine (for you, this would mean the neck). What actually happens is that the bone that protects the spinal cord becomes narrower. This causes pressure at different points on the spinal cord or nerve roots (causing numbness or other symptoms). Here's a great article which might help http://www.niams.nih.gov/health_info/spinal_stenosis/