“Secondment” is a term that came into use in the British military when an officer in one regiment would be embedded in another regiment on assignment for a limited duration. In business, it refers to placing a professional from one business in another business to perform an assignment for a limited time and set cost. Secondment of lawyers first became common in England before spreading to Australia, Singapore, Germany, and more recently the United States. Seconded lawyers can work at the offices of business clients as in-house counsel. Lawyers can also be seconded to other law firms to assist with overflow work, trial preparation, and as cover for attorney absences.

Pronunciation: https://dictionary.cambridge.org/us/pronunciation/english/secondment