All 5 Uses of

reflection
in
Lord of the Flies

The palms that still stood made a green roof, covered on the underside with a quivering tangle of reflections from the lagoon.
p. 12.4

reflections = light seen after bouncing off a surface to another

Then he sat carefully on a fallen trunk near the little cliff that fronted the lagoon; and the tangled reflections quivered over him.
p. 14.9 *

reflections = light that bounced off a surface

He peered at his reflection and disliked it.
p. 63.5

reflection = an image (seen on a mirror or other shiny surface)

He looked in the pool for his reflection, but his breathing troubled the mirror.
p. 63.8 *

reflection = image (on the surface of the pool)

Normally the underside of the green roof was lit by a tangle of golden reflections, and their faces were lit upside down—like, thought Ralph, when you hold an electric torch in your hands.
p. 77.9

reflections = light seen after bouncing off a surface to another

Definitions:

(1) (reflection as in: my reflection in the mirror)
an image (seen on a mirror or other shiny surface)
(2) (reflection as in: lit by the reflection)
light seen after it bounces off a surface to another; or the process of bouncing light, sound, or other energy off of a surface
(3) (reflection as in: is a reflection of American values)
something that indirectly shows something else -- such as an indication, demonstration, expression, or representation of something
The exact meaning of this sense of reflection depends upon its context. For example:
- "The students' behavior is a reflection on the school." -- indication of quality
- "She says the immorality in the movie is a reflection of American values." -- expression or representation
- "It was a reflection of the selfishness she had seen growing for years." -- demonstration
- "The surrounding panic found no reflection in her." -- expression or demonstration
- "I saw no reflection of jealousy in her action." -- indication or sign
(4) (reflection as in: After reflection, I think...)
careful thought
(5) (reflection as in: a humbling reflection (memory))
memories and thoughts about them
(6) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

See a comprehensive dictionary for less common meanings of reflection.