sick·ness 
/ˈsɪknəs/ noun
plural sick·ness·es /ˈsɪknəs/ noun 1 [noncount] : unhealthy condition of body or mind : the state of being sick
▪ She missed work due to sickness. [=illness] 2 [count] : a specific type of disease or illness
▪ He died from an unknown sickness. — see also radiation sickness, sleeping sickness 3 [noncount] : the feeling you have in your stomach when you think you are going to vomit
▪ The patient complained of sickness [=nausea] and stomach pains. — see also morning sickness, motion sickness, travel sickness
▪ She missed work due to sickness. [=illness]
▪ He died from an unknown sickness. — see also radiation sickness, sleeping sickness
▪ The patient complained of sickness [=nausea] and stomach pains. — see also morning sickness, motion sickness, travel sickness
