Legal jargon that denotes that someone’s legal position has been harmed or weakened. The term prejudice is used in many contexts, including dismissing of cases without prejudice or with prejudice, in the context of settlement discussions “without prejudice“, and in certain equitable defences such as equitable estoppel and laches.
Outside the procedural context the existence of prejudice is a fact specific issue. A wide variety of facts can raise to suggest “prejudice,” for example, loss of evidence due to time, accreting of avoidable damages, making irreversible design decisions, making otherwise avoidable investments, loss of the ability to file a claim or counterclaim, substantial; weakening of legal rights, loss of the ability to seek an indemnity.