/ˈfəʊkəs ||; ˈfokəs/noun [C] (
plural focuses or foci /ˈfəʊsaɪ
||; ˈfosaɪ/)
1 [usu.sing] the centre of interest or attention; special attention that is given to sb/sth 兴趣或注意力的中心；对…特别注意: The school used to be the focus of village life. 以前这学校是农村生活的中心。
2 (also focal point) (technical术语) a point at which rays or waves of light, sound, etc meet after REFLECTION or REFRACTION; the point from which rays or waves of light, sound, etc. seem to come （光、声等的）焦点，中心点
in focus/out of focus (used about a photograph or sth in a photograph) clear/not clear （指照片或照片上的东西）清楚或不清楚:
This picture is so badly out of focus that I can't recognize anyone. 这张照片照得极不清楚，上面的人我一个也认不出来。