I believe this is a sort of contraction for the phrase "hunk of junk". The preposition of often becomes "a" in rapid speech. Ex It is made of steel. It is made a steel. The meaning of hunk of junk is "a pile of junk" Ex. My car is old and often does not start, it is a hunk of junk. Hope this helps! John

Hunkajunk or hunk of junk is used to refer to something crappy and worthless.

It is pretty much slang. It means a piece of junk. Something that is old and worn and doesn't work any more. An old bike or an old car....

I have never heard this phrase, what was the trailer for?