| Term | Definition |
| debilitate | v. impair the strength of;enfeeble;weaken |
| decadent | adj. marked by decay or decline;deteriorating |
| decrepit | adj. broken down or weakened by old age or use |
| dilapidated | adj. falling to pieces; decayed; partly ruined |
| enervate | v. lessen the vigor or strength of; weaken |
| flimsy | adj. lacking strength or solidity;frail |
| frail | adj. not very strong;weak; fragile |
| incapacitate | v. render incapable or unfit; disable |
| infirmity | n.weakness; feebleness; fraility |
| bulwark | n.wall-like defensive structure; rampart; defense |
| citadel | n.fortess;stronghold |
| cogent | adj. forcible;compelling; powerful |
| dynamic | adj. forceful; energetic;active |
| formidable | adj. exciting fear by reason of strength, size, difficulty |
| forte | n. strong point; that which one does with excellence |
| impregnable | adj. incapable of being taken by assault |
| invigorate | v. give vigor to; fill with life and energy;animate |
| robust | adj. strong and healthy; vigorous; sturdy |
| tenacious | adj. holding fast or tending to hold fast |
| vehement | adj. showing strong feeling; forceful; violent |
| vigor | n. active strength or force; energy |