Spinach : Associated with strength. Remember Popeye?

Spiral : Dreaming of a spiral possibly denotes progress and evolution.

Stadium : Dream of stadium probably has something to do with the qualities that a stadium implies to you. It could be related to a sense of spectatorship or being at the focus of attention.

Staircase : Flight of staircase, esoterically, it symbolises the planes or dimensions of consciousness.

Steam : Steam appearing in the dream may denote having the feeling of anger. Steam coming from the ground represents  repressed anger that is about to surface.

Swamp, marsh : Areas in one’s life that are stagnating or not making much  progress. The conditions of the water in the swamp may be indicative of the  associative  emotional condition.Mud may represent complicated emotional issues and problems.
Swimming : could be indicative of how we handle emotions and feelings. For example:  Struggling to keep afloat in the dream may reflect the struggle we have with our emotional conditions.  Similarly, having an easy swimming may denote emotional confidence.

Shampoo : 1. Improving connection to Divine.
2. Spiritual cleansing.

Sheep : Denotes qualities associated with the animal such as lack of individuality.

Ship : 1. Dealing with significant emotional issues.
2. A major transformation.

Shoe : Associated with one’s approach to life. Possible interpretations:
1. Seeing from another person’s viewpoint. Be in somebody’s shoe.
2. Something/skills/knowledge that needs to be incorporated into ones’ life.
3. Changing shoes may mean a change of duty or role.

4. Forgetting to wear shoe may mean letting go of restraints.

Snow : Related to water. Water is associated with emotion.
Snow may mean any of the following:
1. Freezing one’s emotion.
2. Cleansing, rejuvenation or purification

Somersault : If one dreamed of a friend  doing the somersault, it is a warning to look out for deception by the person involved. If you performed the somersault yourself, you will overcome your present difficulties sooner than you expect.

School, university : 1. May be related to some issues that  originated during younger school days.
2. Dreaming of being in school or university could be symbolic of lessons in life.

Seashell : 1. Associated with self-protection and security.
2. May indicate unusual experiences and/or events.

Seesaw : 1. Symbolises indecisiveness and procrastination. 2. Trying to strike a balance.

Having sex : 1.  Could  possibly be a release mechanism for repressed sexual tensions.
2. Could also signify the integration with an aspect of self (which is symbolised by the sex partner in the dream)

Sewer : To be in one may denote being in an unpleasant or negative situation.