boron

[ bawr-on, bohr- ]

noun

, Chemistry.

1. a nonmetallic element occurring naturally only in combination, as in borax or boric acid, and obtained in either an amorphous or a crystalline form when reduced from its compounds. : B; : 10.811; : 5.

boron

/ ˈbɔːrɒn /

noun

1. a very hard almost colourless crystalline metalloid element that in impure form exists as a brown amorphous powder. It occurs principally in borax and is used in hardening steel. The naturally occurring isotope boron-10 is used in nuclear control rods and neutron detection instruments. Symbol: B; atomic no: 5; atomic wt: 10.81; valency: 3; relative density: 2.34 (crystalline), 2.37 (amorphous); melting pt: 2092°C; boiling pt: 4002°C

boron

/ bôr′ŏn′ /

1. A shiny, brittle, black metalloid element extracted chiefly from borax. It is a good electrical conductor at high temperatures and a poor conductor at low temperatures. Boron is necessary for the growth of land plants and is used in the preparation of soaps, abrasives, and hard alloys. It is also used in the control rods of nuclear reactors as a neutron absorber. Atomic number 5; atomic weight 10.811; melting point 2,300°C; sublimation point 2,550°C; specific gravity (crystal) 2.34; valence 3.
2. See Periodic Table

Other Words From

• bo·ron·ic [boh-, ron, -ik, baw-, b, uh, -], adjective

Word History and Origins

Origin of boron¹

1805–15; bor(ax ¹ ) + (carb)on

Word History and Origins

Origin of boron¹

C19: from bor ( ax ) + ( carb ) on

Example Sentences

His results indicated that fruits are relatively rich in boron.

From Project Gutenberg

Tobacco is so rich in boron that it can be detected in the ash of one cigarette.

From Project Gutenberg

Before the introduction of Gooch's process it was usual to determine the boron trioxide "by difference."

From Project Gutenberg

Consequently, the increase in weight, after ignition, upon that of the lime taken gives the amount of boron trioxide present.

From Project Gutenberg

There is only one series of boron compounds which have any importance.

From Project Gutenberg