nab

Etymology 1

From dialectal nap (“to seize, lay hold of”), probably of North Germanic origin, from Old Swedish nappa (“to pluck, pinch”). Related to Danish nappe (“to tweak, snatch at, catch, seize”), Swedish nappa (“to take, grab, pinch”), Norwegian Bokmål nappe (“to grab, snatch, pluck, yank”).

verb

1. (informal, transitive) To seize, arrest or take into custody (a criminal or fugitive).
   As I was going out of the door, a fellow detective came hurriedly in. "Nabbed them," cried he. 1887, Anna Katharine Green, 7 to 12, A Detective Story, G. P. Putnam's Sons, page 2
   Their target: a drug kingpin who reportedly keeps millions of dollars in his fortress of a compound. Pope has been working for years to nab this baddie, and sincerely wants to stop his reign of terror,) 3 July 2019, Mike D'Angelo, “Oscar Isaac and Ben Affleck blunder through a heavy heist in J.C. Chandor’s Triple Frontier”, in AV Club
2. (informal, transitive) To grab or snatch something.

Etymology 2

Compare knap, knop, knob.

noun

1. The summit of a hill.
   At Clayton point and other nabs to the south of Scarborough. 1828, George Young, A Geological Survey of the Yorkshire Coast
2. The cock of a gunlock.
3. (locksmithing) The keeper, or box into which the lock is shot.
   the Bottom of the Bit may fall almost to the Bottom of the Nab , and shoot the Bolt back 1703, Joseph Moxon, Mechanick Exercises