What Causes Large Floater In Eye Blocking The Vision?

i noticed that my left eye all of a sudden has a large floater which blocks some of my vision. if i close my right eye everything is clear in left eye if i look @ words it looks as if im looking though a tinted glass which makes the words blurry. i was wearing contacts in the time but only on the weekends my eyes dont hurt i do have allergies if that makes them worse. but it really messes me up makes me feel disorented with my glasses on. hope this helps oh if i blink in the eye thats bad it looks like i have the image of my contact or as if you looked into a light then tried to look around hard to focus. thanks Greg.