(~s)
1.
A ~ of something is a very small piece or amount of it.
There is a ~ of truth in his statement.
...food ~s.
N-COUNT: oft N of n
2.
In physics, a ~ is a piece of matter smaller than an atom, for example an electron or a proton. (TECHNICAL)
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3.
In grammar, a ~ is a preposition such as ‘into’ or an adverb such as ‘out’ which can combine with a verb to form a phrasal verb.
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