1) Badly 2) Debile 3) Dimly 4) Feebly 5) Frail 6) Incompetently 7) Insipidly 8) Lightly 9) Poorly 10) Powerlessly 11) Reluctantly 12) Sapless 13) Softly 14) Unconvincingly 15) Untenably 1) Decrepit 2) Feeble 3) Frail 4) How a blooper is hit 5) In a feeble manner 6) Infirm 7) Sapless 8) Weak 9) Without conviction 10) Without strength 
• (adv.) In a weak manner; with little strength or vigor; feebly. • (superl.) Not strong of constitution; infirm; feeble; as, a weakly woman; a man of a weakly constitution.
Weak'ly adjective [ Compar. Weaklier ; superl. Weakliest .] Not strong of constitution; infirm; feeble; as, a weakly woman; a man of a weakly constitution. Weak'ly adverb In a weak manner; with little strength or vigor; feebly. 
[adv] - in a weak or feeble manner or to a minor degree