One who enters property of another without permission. A property owner generally is obligated to avoid intentional injury to trespassers and do so by a full disclosure of all information material to the proposed contract.
one who goes on another's premises without permission. A property owner owes a trespasser a lower degree of care (i.e. the "duty owed" element of NEGLIGENCE) than he does an INVITEE or LICENSEE. His duty to a trespasser is to not willfully cause injury to him. The concept of ATTRACTIVE NUISANCE is an exception to this.
An individual who goes onto another person's property without any legal right to do so. The only duty that the owner of the property owes a trespasser is not to intentionally harm or set a trap for him.