Adjective

(en adjective)

Done merely to discharge a duty; performed mechanically and as a thing of rote; done in a careless and superficial manner; characterized by indifference; as, perfunctory admonitions; aspiring only to minimum standards.

He did a perfunctory job cleaning his dad's car, finishing quickly but leaving a few spots still dirty.

* 1918 , (Edgar Rice Burroughs), Chapter VIII

I caught the gist of what he was saying--which in effect was that he had found and captured this Galu, that she was his and that he defied anyone to question his right of possession. It appeared to me, as I afterward learned was the fact, that I was witnessing the most primitive of marriage ceremonies. The assembled members of the tribe looked on and listened in a sort of dull and perfunctory apathy, for the speaker was by far the mightiest of the clan.

* 1992 , Peter Bowbrick, The Economics of Quality, Grades, and Brands , p. 55,

Alternatively it may mean that a perfunctory search is enough to ensure that a purchase is acceptable, so less search is carried out.

Adjective

(er)

Lax; not tense; not hard drawn; not firmly extended.

a slack rope

Weak; not holding fast.

a slack hand

Remiss; backward; not using due diligence or care; not earnest or eager.

slack in duty or service

* Bible, 2 Peter iii. 9

The Lord is not slack concerning his promise, as some men count slackness.

Not violent, rapid, or pressing.

Business is slack .

* {{quote-book, year=1928, author=Lawrence R. Bourne

, title=Well Tackled! , chapter=3 citation , passage=“They know our boats will stand up to their work,” said Willison, “and that counts for a good deal. A low estimate from us doesn't mean scamped work, but just for that we want to keep the yard busy over a slack time.”}}

(slang, West Indies) vulgar; sexually explicit, especially in dancehall music