The term 'in depth' is often used to describe something that is COMPREHENSIVE and THOROUGH. The two crossword solutions for this term are 'COMPREHENSIVE' (13 letters) and 'THOROUGH' (8 letters). Both words imply a level of detail and understanding that goes beyond the surface level. COMPREHENSIVE means to cover or include all aspects of a subject, while THOROUGH means to be done with great care and attention to detail. In other words, when something is described as being in depth, it means that it has been studied and understood in great detail.