glaze_over
1. [ verb ] become glassy; lose clear vision
Synonyms: blur film_over
Examples:

"Her eyes glazed over from lack of sleep"

Related terms: blur
2. [ verb ] become glassy or take on a glass-like appearance
Synonyms: glaze glass_over glass
Examples:

"Her eyes glaze over when she is bored"

Related terms: change
Similar spelling:   gloss_over
  glass_over