He plans to 'thin' (out) the young carrots in the garden. [=to remove some of them so that there is more room between the remaining carrots]
His hair is a little 'thin' on top. = He's a little 'thin' on top. [=he does not have a lot of hair on the top of his head]
The bank's decision to raise rates could be 'the thin end of the wedge'. [=many other banks may also decide to raise rates]
(..) ...it courses through the natural gates and alleys of the body, and with a sudden vigour... ...it doth posset and curd, like acid dropping into milk, the thin and wholesome blood So did it mine. And soon a foul eruption barked about, most leper-like... ...with vile and loathsome crust, (..)2015 Hamlet