made weak by old age or hard use

deteriorated, debilitated, especially as a result of age

the part of a story or drama (after the climax) when the leading character suffers (before the final catastrophe or resolution)

dropping

almost collapsing

falling apart; in poor condition

(of a person, movements etc) weak; unsteady; unsafe

trembling

likely to throw up food from the stomach; ill; not well

not healthy, not feeling well

not sound

not well; flimsy

not firm or steady

shaky

not steady

shaky