Which adapter should I buy?

[Raghav]

I am a complete plumbing newbie. The hose that connects my sprinkler system to the tap disconnected and is no longer staying connected after several tries. Which adapter should I buy to connect? (See images for details)

In the image top facet goes to sprinkler, bottom goes to tap. One the top one it says "Dic npt".

Below is the image of the original adapter which no longer keeps the two connected

 

[Terry]

NPT National Pipe Thread = 3/4" tapered pipe thread in this case
The hose is a 3/4" hose thread.
They make a fitting that has a 3/4 NPT by 3/4 hose thread.