Lightweight

[lahyt-weyt] /ˈlaɪtˌweɪt/

adjective
1.
in .
2.
being in , texture, etc., than another item or object of identical use, quality, or function:
a lightweight topcoat; a lightweight alloy for ship construction.
3.
without seriousness of purpose; trivial or trifling:
lightweight reading.
4.
of or relating to a lightweight:
He’s the new lightweight contender.
5.
(of a horse, especially a hunter) able to carry up to 165 pounds (75 kg).
noun
6.
a person of less than average .
7.
Informal. a person who is of little influence, importance, or effect.
8.
a boxer or other contestant intermediate in between a featherweight and a welterweight, especially a professional boxer weighing between 126 and 135 pounds (56.7–61 kg).
/ˈlaɪtˌweɪt/
adjective
1.
of a relatively light weight
2.
not serious; trivial
noun
3.
a person or animal of a relatively light weight
4.

5.
a wrestler in a similar weight category (usually 115–126 pounds (52–57 kg))
6.
(informal) a person of little importance or influence
adj.

also light-weight, 1773 in horse-racing, also in pugilism; from light (adj.1) + weight. Figurative sense of “inconsequential” first attested 1809.

adjective

Inconsequential; unserious (1809+)

noun

: He seems like a lightweight to me, don’t pay him any attention (1882+)