be diseased, impotent folk (man), (be) sick, (be, be made) weak

Boyd’s Bible Dictionary:

(uneasy). Visitations of plagues and pestilences frequent in Bible lands (Gen. 7-8; Ex. 12:21-29; 2 Kings 19:35; 1 Chron. 21:12; Acts 12:23). Principal bodily diseases were, ophthalmia, leprosy, brain and malarial fevers, lung disorders.

Concise Bible Dictionary:

There are four Hebrew words and four Greek words so translated, but, like the English word, they do not specify the nature of the complaint. God promised to Israel that if they would be obedient He would take away from them all sickness, and would put upon them none of the evil diseases of Egypt which they had known (Deut. 7:15). When the Lord was on earth He healed every sickness and every disease among the people (Matt. 9:35). On the ground of obedience they failed to attain freedom from diseases, but their Messiah healed them all in grace. See the various names of the specific diseases, as FEVER.

Strong’s Dictionary of Greek Words:

Number:

770 (find all occurrences in KJV Bible)

Greek:

ἀσθενέω

Transliteration:

astheneo

Phonic:

as-then-eh’-o

Meaning:

from 772; to be feeble (in any sense)

KJV Usage:

be diseased, impotent folk (man), (be) sick, (be, be made) weak