1. [n]  a thrumming sound; "he could hear the thrum of a banjo"
2. [v]  make a rhythmic sound; "Rain drummed against the windshield"; "The drums beat all night"
3. [v]  sound the strings of (a guitar or similar string instrument)
4. [v]  sound with a monotonous hum

Thrum
Thrum

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1. \Thrum\, n. [OE. thrum, throm; akin to OD. drom, D. dreum,
   G. trumm, lump, end, fragment, OHG. drum end, Icel. ?r["o]mr
   edge, brim, and L. terminus a limit, term. Cf. {Term}.]
   [Written also {thrumb}.]
   1. One of the ends of weaver's threads; hence, any soft,
      short threads or tufts resembling these.
   2. Any coarse yarn; an unraveled strand of rope.
   3. (Bot.) A threadlike part of a flower; a stamen.
   4. (Mining) A shove out of place; a small displacement or
      fault along a seam.
   5. (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.
   

2. \Thrum\, v. t. [imp. & p. p. {Thrummed}; p. pr. & vb. n.
   {Thrumming}.]
   1. To furnish with thrums; to insert tufts in; to fringe.
            Are we born to thrum caps or pick straw? --Quarles.
   2. (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.
   

3. \Thrum\, v. i. [CF. Icel. ?ruma to rattle, to thunder, and
   E. drum.]
   1. To play rudely or monotonously on a stringed instrument
      with the fingers; to strum.
   2. Hence, to make a monotonous drumming noise; as, to thrum
      on a table.
   

4. \Thrum\, v. t.
   1. To play, as a stringed instrument, in a rude or monotonous
      manner.
   2. Hence, to drum on; to strike in a monotonous manner; to
      thrum the table.