little seeds that stick to your clothes from walking in the woods. It's a humorous term and suggest the "victim" could not get real lice and could only get beggar's "lice".

beg·gar's lice (bgrz)
n. (used with a sing. or pl. verb)
1. Any of several plants, such as the stickseed, having small, often prickly fruits that cling readily to clothing or animal fur.
2. The fruit of any of these plants.
I justed came from a hike and my pants are covered with beggar's lice.
by sylvain1997 January 3, 2011
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