trembling β to shake involuntarily with quick, short movements, as from fear, excitement, weakness, or cold; quake; quiver.
insecure β subject to fears, doubts, etc.; not self-confident or assured: an insecure person.
jittery β extremely tense and nervous; jumpy: He's very jittery about the medical checkup.
nervous β highly excitable; unnaturally or acutely uneasy or apprehensive: to become nervous under stress.
precarious β dependent on circumstances beyond one's control; uncertain; unstable; insecure: a precarious livelihood.
rickety β likely to fall or collapse; shaky: a rickety chair.
rocky β inclined or likely to rock; tottering; shaky; unsteady.
unsettled β not settled; not fixed or stable; without established order; unorganized; disorganized: an unsettled social order; still unsettled in their new home.
unstable β not stable; not firm or firmly fixed; unsteady.
unsteady β not steady or firm; unstable; shaky: an unsteady hand.
weak β not strong; liable to yield, break, or collapse under pressure or strain; fragile; frail: a weak fortress; a weak spot in armor.
infirm β feeble or weak in body or health, especially because of age; ailing.
jellylike β a food preparation of a soft, elastic consistency due to the presence of gelatin, pectin, etc., especially fruit juice boiled down with sugar and used as a sweet spread for bread and toast, as a filling for cakes or doughnuts, etc.