Michael Heap and Kottiyattl Aravind in their excellent book, Hartland's Medical and Dental Hypnosis define hypnosis as follows (p.55):

The term 'hypnosis' is used to denote an interaction between two people (or one person and a group) in which one of them, the hypnotist, by means of verbal communication, encourages the other, the subject or subjects, to focus their attention away from their immediate realities and concerns and on inner experiences such as thoughts, feelings and imagery. The hypnotist further attempts to create alterations in the subjects' sensations, perceptions, feelings, thoughts and behaviour by directing them to imagine various events or situations that, were they to occur in reality, would evoke the intended changes.

DEFINITIONS OF STRESS

In the past four decades, a number of useful definitions of stress have been developed by researchers. We provide a range of these below: 

Stress arises when individuals perceive that they cannot adequately cope with the demands being made on them or with threats to their well-being. R.S. Lazarus (1966). Psychological stress and the coping process. New York: McGraw-Hill. 

Stress, it is argued, can only be sensibly defined as a perceptual phenomenon arising from a comparison between the demand on the person and his or her ability to cope. An imbalance in this mechanism, when coping is important, gives rise to the experience of stress, and to the stress response. T. Cox (1978). Stress. Basingstoke: Macmillan Education. 

Stress results from an imbalance between demands and resources. R.S. Lazarus and S. Folkman (1984). Stress, Appraisal and Coping. New York: Springer. 

Stress is the psychological, physiological and behavioural response by an individual when they perceive a lack of equilibrium between the demands placed upon them and their ability to meet those demands, which, over a period of time, leads to ill-health. S. Palmer (1989). Occupational stress. The Health and Safety Practitioner, 7, (8), 16-18. 

A simple definition that can be used is: Stress occurs when pressure exceeds your perceived ability to cope. 

S. Palmer, 1999.