Felt grainFelt grain\, the grain of timber which is transverse to the annular rings or plates; the direction of the medullary rays in oak and some other timber. --Knight. Felt \Felt\, v. t. [imp. & p. p. Felted; p. pr. & vb. n. Felting.]1. To make into felt, or a feltike substance; to cause to adhere and mat together. --Sir M. Hale. 2. To cover with, or as with, felt; as, to felt the cylinder of a steam emgine.