pound sand

verb
RareNot in standard dictionaries
1

To engage in a simple, useless activity that anyone would reasonably know how to perform.

2

To engage in a futile activity.

3

To go away; get lost; go to hell; to waste one's own time (with some other meaningless task) rather than waste the speaker's time with something equally irritating or pointless.

#derogatory#informal#slang