'Pillow block' definitions:

Definition of 'pillow block'

noun

A cast-iron or steel block for supporting a journal or bearing

From: GCIDE

Pillow \Pil"low\, n. [OE. pilwe, AS. pyle, fr. L. pilvinus.]
1. Anything used to support the head of a person when reposing; especially, a sack or case filled with feathers, down, hair, or other soft material. [1913 Webster]
[Resty sloth] finds the down pillow hard. --Shak. [1913 Webster]
2. (Mach.) A piece of metal or wood, forming a support to equalize pressure; a brass; a pillow block. [R.] [1913 Webster]
3. (Naut.) A block under the inner end of a bowsprit. [1913 Webster]
4. A kind of plain, coarse fustian. [1913 Webster]
Lace pillow, a cushion used in making hand-wrought lace.
Pillow bier [OE. pilwebere; cf. LG. b["u]re a pillowcase], a pillowcase; pillow slip. [Obs.] --Chaucer.
Pillow block (Mach.), a block, or standard, for supporting a journal, as of a shaft. It is usually bolted to the frame or foundation of a machine, and is often furnished with journal boxes, and a movable cover, or cap, for tightening the bearings by means of bolts; -- called also pillar block, or plumber block.
Pillow lace, handmade lace wrought with bobbins upon a lace pillow.
Pillow of a plow, a crosspiece of wood which serves to raise or lower the beam.
Pillow sham, an ornamental covering laid over a pillow when not in use.
Pillow slip, a pillowcase. [1913 Webster]