What is a TrundleBum?

From Merriam-Webster

Main Entry: trun·dle
Function: verb
Inflected Form(s): trun·dled; trun·dling
Etymology: 2trundle
Date: circa 1598

transitive verb
1 to propel by causing to rotate:
2. roll "a…child who was trundling a hoop" — Charles Dickens: barchaic
to cause to revolve or spin
3. to transport in or as if in a wheeled vehicle : haul wheel
"trundled him off to school"

intransitive verb
1. to progress by revolving
2. to move on or as if on wheels : roll
"buses trundling through the city"
— trun·dler noun

Bum

From Merriam-Webster

Main Entry: Bum
Function: noun
Etymology: Middle English bom
Date: 14th century

Function: adjective
1 a: of poor quality or nature "bum advice"
b: not valid or deserved "a bum check"
c: not pleasant or enjoyable "a bum trip"
2. affected or disabled by damage or injury

Function: verb
1. loaf
2. to spend time unemployed and often wandering
transitive verb: to obtain by asking or begging
cadge "bum a cigarette"

Function: noun
1 a: one who sponges off others and avoids work
b: one who performs a function poorly "called the umpire a bum"
c: one whose time is devoted to a recreational activity
"a beach bum" "ski bums"

"Climbing Bums"

Trundle

Trundling

To trundle (a boulder):
In climber terms means to gently assist gravity in setting a large stone in motion.
This is occasionally done to clear a climbing crag of potential future rock fall.
It is potentially very dangerous both to the trundler and anybody the vicinity of the trundling act.

It is not a good practise to get into unless highly warranted
If you feel that trundling a potentially dangerous rock is justified,
make sure you take great precautions to look for and warn anybody below.
Even a marble sized fragment that ricochets can become lethal.