The Collaborative International Dictionary of English v.0.48:

Plane \Plane\, n. [F., fr. L. platanus, Gr. ?, fr. ? broad; --
   so called on account of its broad leaves and spreading form.
   See Place, and cf. Platane, Plantain the tree.] (Bot.)
   Any tree of the genus Platanus.
   [1913 Webster]

   Note: The Oriental plane (Platanus orientalis) is a native
         of Asia. It rises with a straight, smooth, branching
         stem to a great height, with palmated leaves, and long
         pendulous peduncles, sustaining several heads of small
         close-sitting flowers. The seeds are downy, and
         collected into round, rough, hard balls. The Occidental
         plane (Platanus occidentalis), which grows to a great
         height, is a native of North America, where it is
         popularly called sycamore, buttonwood, and
         buttonball, names also applied to the California
         species (Platanus racemosa).
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sycamore \Syc"a*more\, n. [L. sycomorus, Gr. ? the fig mulberry;
   ? a fig + ? the black mulberry; or perhaps of Semitic origin:
   cf. F. sycomore. Cf. Mulberry.] (Bot.)
   (a) A large tree (Ficus Sycomorus) allied to the common
       fig. It is found in Egypt and Syria, and is the sycamore,
       or sycamine, of Scripture.
   (b) The American plane tree, or buttonwood.
   (c) A large European species of maple (Acer
       Pseudo-Platanus). [Written sometimes sycomore.]
       [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Buttonwood \But"ton*wood`\, n. (Bot.)
   The Platanus occidentalis, or American plane tree, a large
   tree, producing rough balls, from which it is named; --
   called also buttonball tree, and, in some parts of the
   United States, sycamore. The California buttonwood is
   Platanus racemosa.
   [1913 Webster]

WordNet (r) 3.0 (2006):

sycamore
    n 1: variably colored and sometimes variegated hard tough
         elastic wood of a sycamore tree [syn: sycamore,
         lacewood]
    2: any of several trees of the genus Platanus having thin pale
       bark that scales off in small plates and lobed leaves and
       ball-shaped heads of fruits [syn: plane tree, sycamore,
       platan]
    3: Eurasian maple tree with pale grey bark that peels in flakes
       like that of a sycamore tree; leaves with five ovate lobes
       yellow in autumn [syn: sycamore, great maple, scottish
       maple, Acer pseudoplatanus]
    4: thick-branched wide-spreading tree of Africa and adjacent
       southwestern Asia often buttressed with branches rising from
       near the ground; produces cluster of edible but inferior figs
       on short leafless twigs; the biblical sycamore [syn:
       sycamore, sycamore fig, mulberry fig, Ficus
       sycomorus]

Easton's 1897 Bible Dictionary:

Sycamore
   more properly sycomore (Heb. shikmoth and shikmim, Gr.
   sycomoros), a tree which in its general character resembles the
   fig-tree, while its leaves resemble those of the mulberry; hence
   it is called the fig-mulberry (Ficus sycomorus). At Jericho,
   Zacchaeus climbed a sycomore-tree to see Jesus as he passed by
   (Luke 19:4). This tree was easily destroyed by frost (Ps.
   78:47), and therefore it is found mostly in the "vale" (1 Kings
   10:27; 2 Chr. 1:15: in both passages the R.V. has properly
   "lowland"), i.e., the "low country," the shephelah, where the
   climate is mild. Amos (7:14) refers to its fruit, which is of an
   inferior character; so also probably Jeremiah (24:2). It is to
   be distinguished from our sycamore (the Acer pseudo-platanus),
   which is a species of maple often called a plane-tree.


U.S. Gazetteer Places (2000):

Sycamore, GA -- U.S. city in Georgia
   Population (2000):    496
   Housing Units (2000): 209
   Land area (2000):     0.997241 sq. miles (2.582841 sq. km)
   Water area (2000):    0.002461 sq. miles (0.006374 sq. km)
   Total area (2000):    0.999702 sq. miles (2.589215 sq. km)
   FIPS code:            75104
   Located within:       Georgia (GA), FIPS 13
   Location:             31.670810 N, 83.633871 W
   ZIP Codes (1990):     31790
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Sycamore, GA
    Sycamore


U.S. Gazetteer Places (2000):

Sycamore, OH -- U.S. village in Ohio
   Population (2000):    914
   Housing Units (2000): 401
   Land area (2000):     0.587989 sq. miles (1.522884 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.587989 sq. miles (1.522884 sq. km)
   FIPS code:            75980
   Located within:       Ohio (OH), FIPS 39
   Location:             40.950402 N, 83.170919 W
   ZIP Codes (1990):     44882 45242 45249
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Sycamore, OH
    Sycamore


U.S. Gazetteer Places (2000):

Sycamore, OK -- U.S. Census Designated Place in Oklahoma
   Population (2000):    183
   Housing Units (2000): 59
   Land area (2000):     4.144380 sq. miles (10.733895 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    4.144380 sq. miles (10.733895 sq. km)
   FIPS code:            71965
   Located within:       Oklahoma (OK), FIPS 40
   Location:             36.401443 N, 94.713463 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Sycamore, OK
    Sycamore


U.S. Gazetteer Places (2000):

Sycamore, OK -- U.S. Census Designated Place in Oklahoma
   Population (2000):    150
   Housing Units (2000): 79
   Land area (2000):     7.053526 sq. miles (18.268547 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    7.053526 sq. miles (18.268547 sq. km)
   FIPS code:            71972
   Located within:       Oklahoma (OK), FIPS 40
   Location:             35.519520 N, 94.941129 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Sycamore, OK
    Sycamore


U.S. Gazetteer Places (2000):

Sycamore, IL -- U.S. city in Illinois
   Population (2000):    12020
   Housing Units (2000): 4925
   Land area (2000):     5.484594 sq. miles (14.205033 sq. km)
   Water area (2000):    0.017968 sq. miles (0.046537 sq. km)
   Total area (2000):    5.502562 sq. miles (14.251570 sq. km)
   FIPS code:            74223
   Located within:       Illinois (IL), FIPS 17
   Location:             41.983850 N, 88.694091 W
   ZIP Codes (1990):     60178
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Sycamore, IL
    Sycamore


U.S. Gazetteer Places (2000):

Sycamore, SC -- U.S. town in South Carolina
   Population (2000):    185
   Housing Units (2000): 93
   Land area (2000):     3.171566 sq. miles (8.214319 sq. km)
   Water area (2000):    0.009319 sq. miles (0.024137 sq. km)
   Total area (2000):    3.180885 sq. miles (8.238456 sq. km)
   FIPS code:            70900
   Located within:       South Carolina (SC), FIPS 45
   Location:             33.038490 N, 81.222032 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Sycamore, SC
    Sycamore


U.S. Gazetteer Places (2000):

Sycamore, KY -- U.S. city in Kentucky
   Population (2000):    159
   Housing Units (2000): 90
   Land area (2000):     0.027240 sq. miles (0.070551 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.027240 sq. miles (0.070551 sq. km)
   FIPS code:            75190
   Located within:       Kentucky (KY), FIPS 21
   Location:             38.246973 N, 85.560664 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Sycamore, KY
    Sycamore