From WordNet (r) 3.0 (2006) [wn]:
pier
n 1: a platform built out from the shore into the water and
supported by piles; provides access to ships and boats
[syn: pier, wharf, wharfage, dock]
2: (architecture) a vertical supporting structure (as a portion
of wall between two doors or windows)
3: a support for two adjacent bridge spans
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Pier \Pier\, n. [OE. pere, OF. piere a stone, F. pierre, fr. L.
petra, Gr. ?. Cf. Petrify.]
1. (Arch.)
(a) Any detached mass of masonry, whether insulated or
supporting one side of an arch or lintel, as of a
bridge; the piece of wall between two openings.
(b) Any additional or auxiliary mass of masonry used to
stiffen a wall. See Buttress.
[1913 Webster]
2. A projecting wharf or landing place.
[1913 Webster]
Abutment pier, the pier of a bridge next the shore; a pier
which by its strength and stability resists the thrust of
an arch.
Pier glass, a mirror, of high and narrow shape, to be put
up between windows.
Pier table, a table made to stand between windows.
[1913 Webster]