disposition; temperament; nature; mentality; spirit; character; trait; turn of mind

question; inquiry; enquiry

matter

character (of a group, organization, etc.); innate characteristics; make-up; nature; culture

essence; true nature; substance; reality

hostage

quality (of a product or a service)

parenchyma

substantial; real (as opposed to nominal)

malicious; vicious; malignant; underhanded

interpellation

nature; property; disposition