What is Stress ?
Stress is (noun) 1. the force or pres- sure on something Stresses inside the earth create earthquakes. 2. nervous strain caused by an outside influence She has difficulty coping with the stress of the office. People in positions of responsibility often have stress-related illnesses. 3. the loudness of your voice when you pronounce a word or syllable In the word ’emphasis’ the stress is on the first syllable. (NOTE: The plural is stresses.)(verb) to put emphasis on some- thing I must stress the importance of keep- ing the plan secret. Synonym emphasise
source: Easier English, Student Dictionary Upper Intermediate Level