1. dissimilar
Not similar; not alike

2. focus
Adjust your eyes to see something more clearly; to focus your attention on something

3. *The function of a clock is to tell time.
A purpose, role, or job
*The function of a clock is to tell time.

4. Sharp, quick, or alert; easily offended or hurt
sensitive
Sharp, quick, or alert; easily offended or hurt

5. critical Extremely important or absolutely necessary
*Food and water are necessary for living things to survive

6. Something that blocks or gets in the way
obstacle
Something that blocks or gets in the way