(~s)
Frequency: The word is one of the 3000 most common words in English.
1.
Concentration on something involves giving all your attention to it.
Neal kept interrupting, breaking my ~...
We lacked ~ and it cost us the goal and the game.
N-UNCOUNT
2.
A ~ of something is a large amount of it or large numbers of it in a small area.
The area has one of the world’s greatest ~s of wildlife...
There’s been too much ~ of power in the hands of central authorities.
N-VAR: usu N of n
3.
The ~ of a substance is the proportion of essential ingredients or substances in it.
pH is a measure of the ~ of free hydrogen atoms in a solution...
N-VAR: with supp, oft N of n, n N