a quantity of no importance

• it looked like nothing I had ever seen before
• reduced to nil all the work we had done
• we racked up a pathetic goose egg
• it was all for naught
• I didn't hear zilch about it

• nothing
• nil
• nix
• nada
• null
• aught
• cipher
• cypher
• goose_egg
• naught
• zero
• zilch
• zip
• zippo

a code of letters and digits added to a postal address to aid in the sorting of mail

• ZIP_code
• ZIP
• postcode
• postal_code

forceful exertion

• he plays tennis with great energy
• he's full of zip

• energy
• vigor
• vigour
• zip

a fastener for locking together two toothed edges by means of a sliding tab

• slide_fastener
• zip
• zipper
• zip_fastener

close with a zipper

• Zip up your jacket--it's cold

• zip_up
• zipper
• zip

move very fast

• The runner zipped past us at breakneck speed

• travel_rapidly
• speed
• hurry
• zip