Both Uses of

glimpse

in

Milkweed, by Jerry Spinelli

I believed that sooner or later I would catch a glimpse of one coming out of a freshly dead body, or just hanging around, reluctant to leave.†
Chpt 29 *

glimpse = a quick look or partial understanding

As I sailed through the revolving door, I caught a glimpse of red hair in the lobby.†
Chpt 31

Definition:

a quick look or partial understanding

The exact meaning of glimpse can depend upon its context. For example:

"I caught a glimpse of her when I was walking to class." -- a very quick look
"I glimpsed at the headlines." -- looked quickly
"Reading the book gave me a glimpse of the life of a devout Muslim immigrant in America." -- a quick, incomplete view