conducive to good health of body or mind; "a healthful climate"; "a healthful environment"; "healthful nutrition"; "healthful sleep"; "Dickens's relatively healthful exuberance"
a device for showing the operating condition of some system
a signal for attracting attention
(chemistry) a substance that changes color to indicate the presence of some ion or substance; can be used to indicate the completion of a chemical reaction or (in medicine) to test for a particular reaction
a portable shelter (usually of canvas stretched over supporting poles and fastened to the ground with ropes and pegs); "he pitched his tent near the creek"