Meaning of sinking

(noun) a descent as through liquid (especially through water); "they still talk about the sinking of the Titanic"

a slow fall or decline (as for lack of strength); "after several hours of sinking an unexpected rally rescued the market"; "he could not control the sinking of his legs"

a feeling caused by uneasiness or apprehension; "with a sinking heart"; "a sinking feeling in the pit of my stomach"