apart, not, away from
When something is diffuse, it is widely spread out and scattered.
Someone who is diffident is shy, does not want to draw notice to themselves, and is lacking in self-confidence.
If you are indifferent about something, you are uninterested or neutral about it, not caring either in a positive or negative way.
A difference in something is what makes it not like something else; it can also be a change that makes it not like it was before.
unlike in nature or quality or form or degree
when light passes sharp edges or goes through narrow slits the rays are deflected and produce fringes of light and dark bands
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