to be sneezed at

not to be sneezed/sniffed at

  (informal)
1. if something, especially an amount of money, is not to be sneezed at, it is large enough to be worth having And there's the increase in salary to be considered. £3000 extra a year is not to be sneezed at.
2. if something or someone is not to be sneezed at, they are important or dangerous enough to deserve serious attention Goodman is not a man to be sniffed at. (American & Australian informal)
See also: sneeze
References in classic literature ?
Well," ejaculated the staring Major, "I never heard before that a service revolver was a thing to be sneezed at.
Well, of course, I'm not advising you, Rose," he added, "but forty-five thousand ain't to be sneezed at, is it, when it comes in a lump and you own only the surface?
Upon my word as a sportsman, those venison-steaks have a gamy flavor that's not to be sneezed at, I tell you.
Sir Henry," said I, "this is the most liberal proposal I ever had, and one not to be sneezed at by a poor hunter and trader.
When all was said, he was a gentleman in every sense of the word, and that was something not to be sneezed at, wasn't it?
Beats a washboard an' your knuckles, and, besides, it saves at least fifteen minutes in the week, an' fifteen minutes ain't to be sneezed at in this shebang.