nail

[1]	collar , apprehend , arrest , pick up , nab , cop
[2]	smash , boom , blast
[3]	nail down , attach , secure , peg , join , pin , tack , clinch/clench , fasten , fix , focus , rivet , glue
[4]	hit , breeze through , ace , strike , punch , pass with flying colors , sweep through , shoot , sail through
[5]	pinpoint , nail down , settle , secure , resolve , complete , conclude , make final , finalize
[6]	complete

[1]	fastener , fastening , spike , pin
[2]	fingernail , toenail , claw , talon
[3]	bite one's nails , worry , agonize , fret , lose sleep (over) , chafe , suffer , (Colloq) stew (over/about)
[4]	hard/tough as nails , tough , vigorous , hardy cold , unsentimental , unsympathetic , unfeeling
[5]	hit the nail on the head , be accurate , be correct , be precise , be right , put (one's) finger on it
[6]	on the nail , immediately , at once , straight/right away , promptly , without delay , on the spot , (Colloq) (US) on the barrel-head