weaker

Lacking in force (usually strength) or ability.

“The child was too weak to move the boulder.”

Unable to sustain a great weight, pressure, or strain.

“a weak timber; a weak rope”

Unable to withstand temptation, urgency, persuasion, etc.; easily impressed, moved, or overcome; accessible; vulnerable.

“weak resolutions; weak virtue”

Dilute, lacking in taste or potency.

“We were served stale bread and weak tea.”

(grammar) Displaying a particular kind of inflection, including:

That does not ionize completely into anions and cations in a solution.

“a weak acid;  a weak base”

One of the four fundamental forces associated with nuclear decay.

Bad or uncool.

“This place is weak.”

Having a narrow range of logical consequences; narrowly applicable. (Often contrasted with a strong statement which implies it.)

Resulting from, or indicating, lack of judgment, discernment, or firmness; unwise; hence, foolish.

Not having power to convince; not supported by force of reason or truth; unsustained.

“The prosecution advanced a weak case.”

Lacking in vigour or expression.

“a weak sentence; a weak style”

Not prevalent or effective, or not felt to be prevalent; not potent; feeble.

Tending towards lower prices.

“a weak market; wheat is weak at present”

Lacking contrast.

“a weak negative”