(Archaic/slang,Scottish) Roaming without intent, wandering aimlessly for pure pleasure
"Gore spent his time horbgorbling around ineffectively", the writer claimed, meaning that he travelled about in a feckless manner, fumbling, or "mooching", as we'd say here. (Diarmaid O Muirithe, The words we use, The Irish Times, 2010)
The Professor grumbled under his breath for a good five minutes while horbgorbling about the room, then told the students to take a break (Micki Evris, The Seeding)
The other day while horbgorbling the woods and swamps in a local state park drinking beer and idly looking at things, an extraordinarily thing happened. (Steve Daniels, New York State Champion Cedar and Hophornbeam, The Irish Times, 2010)
For once, I don't have an 'official' origin for this endearingly obscure word, however, I did find this tiny discussion on the website for World Wide Words
Following my request for information on this strange word, several subscribers commented that they came across it in Chosen Words by Ivor Brown, published in 1955. Brown said (and for this I am indebted to Ian Paterson) that the word means "to putter about in a feckless ineffective way" and that Brown heard of it in
connection with the trial of a Caithness man for sexual assault on a young girl. The girl said in Court that the defendant was just horbgorbling and no worse, so that the case was dismissed. It was suggested by other subscribers that it is a variant pronunciation (with spelling following it) of "hobgoblin", though this doesn't explain the sense. Mystery not yet solved, I'm afraid.