infirm

(adjective, verb)

adjective

1. lacking bodily or muscular strength or vitality

Similar word(s): frail, debile, decrepit, feeble, rickety, sapless, weak, weakly

2. lacking firmness of will or character or purpose

- infirm of purpose; give me the daggers

Similar word(s): irresolute

Sentences with infirm as an adjective:

- He was infirm of body but still keen of mind, and though it looked like he couldn't walk across the room, he crushed me in debate.

verb

1. To contradict, to provide proof that something is not.

- The thought is that you see an episode of observation, experiment, or reasoning as confirming or infirming a hypothesis depending on whether your probability for it increases or decreases during the episode.