weak vs strength

weak is not a noun while strength is a noun.

Word	Noun	Adjective	Verb	Adverb
weak	No	Yes	No	No
strength	Yes	No	No	No

weak (noun)	strength (noun)
	the property of being physically or mentally strong
	an asset of special worth or utility
	permanence by virtue of the power to resist stress or force
	the amount of energy transmitted (as by acoustic or electromagnetic radiation)
	capability in terms of personnel and materiel that affect the capacity to fight a war
	physical energy or intensity
	capacity to produce strong physiological or chemical effects
	the power to induce the taking of a course of action or the embracing of a point of view by means of argument or entreaty
	the condition of financial success

weak (adjective)	strength (adjective)
wanting in physical strength
overly diluted; thin and insipid
tending downward in price
likely to fail under stress or pressure
lacking bodily or muscular strength or vitality
wanting in moral strength, courage, or will; having the attributes of man as opposed to e.g. divine beings
deficient in magnitude; barely perceptible; lacking clarity or brightness or loudness etc
not having authority, political strength, or governing power
(used of verbs) having standard (or regular) inflection
deficient in intelligence or mental power
deficient or lacking in some skill
(used of vowels or syllables) pronounced with little or no stress