What does "thrum" mean?

Additional senses

1. 2.(Bot.) A threadlike part of a flower; a stamen.
2. 3.(Mining) A shove out of place; a small displacement or fault along a seam.
3. 4.(Naut.) A mat made of canvas and tufts of yarn. Thrum cap, a knitted cap. Halliwell. -- Thrum hat, a hat made of coarse woolen cloth. Minsheu.
4. 5.To furnish with thrums; to insert tufts in; to fringe. Are we born to thrum caps or pick straw Quarles.
5. 6.(Naut.) To insert short pieces of rope-yarn or spun yarn in; as, to thrum a piece of canvas, or a mat, thus making a rough or tufted surface. Totten.
6. 7.To play rudely or monotonously on a stringed instrument with the fingers; to strum.
7. 8.Hence, to make a monotonous drumming noise; as, to thrum on a table.
8. 9.To play, as a stringed instrument, in a rude or monotonous manner.
9. 10.Hence, to drum on; to strike in a monotonous manner; to thrum the table.