flimsy

Short definition from Wiktionary

Adjective

1. 1
   Likely to bend or break under pressure; easily damaged; frail, unsubstantial.
2. 2
   Likely to bend or break under pressure; easily damaged; frail, unsubstantial: Of clothing: very light and thin.
3. 3
   Of an argument, explanation, etc.: ill-founded, unconvincing, weak; also, unimportant; paltry, trivial.
4. 4
   Of a person: lacking depth of character or understanding; frivolous, superficial.
5. 5
   Of a person, their physical makeup, or their health: delicate, frail.

Noun

1. 1
   A thing which is ill-founded, unconvincing, or weak.
2. 2
   Thin typing paper used together with carbon paper in a typewriter to make multiple copies of a document; (countable) a sheet of such paper.
3. 3
   A document printed or typed on such paper: A service certificate.
4. 4
   A document printed or typed on such paper: A banknote; (uncountable) paper money.
5. 5
   A document printed or typed on such paper: The text to be set into pages of magazines, newspapers, etc.; copy.
6. 6
   A hexahedral metal container with a capacity of four imperial gallons (about 18 litres) used by the British Army during World War II to hold fuel.

Verb

1. 1
   To make (something) likely to be easily damaged.
2. 2
   To type or write (text) on a flimsy (“sheet of thin typing paper used together with carbon paper in a typewriter to make multiple copies of a document”) (noun sense 2).
3. 3
   To treat (someone or something) as paltry or unimportant; to demean, to underestimate.