1.Definition: (used of verbs) having standard (or regular) inflection

2.Definition: (used of vowels or syllables) pronounced with little or no stress

"A weak stress on the second syllable"

Related Adjective(s):light, unaccented

3.Definition: deficient in intelligence or mental power

"A weak mind"

4.Definition: deficient in magnitude; barely perceptible; lacking clarity or brightness or loudness etc

"Weak colors", "A weak pulse"

Related Adjective(s):faint

5.Definition: deficient or lacking in some skill

"He's weak in spelling"

6.Definition: lacking bodily or muscular strength or vitality

Related Adjective(s):debile, decrepit, feeble, infirm, rickety, sapless, weakly

7.Definition: likely to fail under stress or pressure

"The weak link in the chain"

8.Definition: not having authority, political strength, or governing power

"A weak president"

9.Definition: overly diluted; thin and insipid

"Weak tea"

Related Adjective(s):washy, watery

10.Definition: tending downward in price

"A weak market for oil stocks"

11.Definition: wanting in moral strength, courage, or will; having the attributes of man as opposed to e.g. divine beings

Related Adjective(s):fallible, frail, imperfect

12.Definition: wanting in physical strength

"A weak pillar"