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¹plane

verb \ˈplān\

planedplan·ing

Definition of PLANE

transitive verb

a : to make smooth or even : level

b : to make smooth or even by use of a plane

: to remove by or as if by planing —often used with away or off

intransitive verb

: to work with a plane

: to do the work of a plane

— plan·er noun

Origin of PLANE

Middle English, from Anglo-French planer, from Late Latin planare, from Latin planus level — more at floor

First Known Use: 14th century

Other Handicraft Terms

biscuit, darn, tambour, wrought

²plane

noun

Definition of PLANE

: any of a genus (Platanus of the family Platanaceae, the plane-tree family) of chiefly deciduous trees with large palmately lobed leaves, flowers in globose heads, and usually scaling bark —called also buttonwood, plane tree, sycamore

Origin of PLANE

Middle English, from Anglo-French, from Latin platanus, from Greek platanos; probably akin to Greek platys broad — more at place

First Known Use: 14th century

³plane

noun

Definition of PLANE

: a tool for smoothing or shaping a wood surface

Illustration of PLANE

Origin of PLANE

Middle English, from Anglo-French, from Late Latin plana, from planare

First Known Use: 14th century

Other Hardware Terms

adze, auger, awl, chock, ferrule, punch, tang

⁴plane

noun

Definition of PLANE

a : a surface in which if any two points are chosen a straight line joining them lies wholly in that surface

b : a flat or level surface

: a level of existence, consciousness, or development <on the intellectual plane>

a : one of the main supporting surfaces of an airplane

b [by shortening] : airplane

Origin of PLANE

Latin planum, from neuter of planus level

First Known Use: 1571

Other Aeronautics/Aerospace Terms

airway, apron, corridor, dirigible, fishtail, flat-hat, vector

⁵plane

adjective

Definition of PLANE

: having no elevations or depressions : flat

a : of, relating to, or dealing with geometric planes

b : lying in a plane <a plane curve>

Origin of PLANE

Latin planus

First Known Use: 14th century

Related to PLANE

Synonyms: even, flat, flush, level, smooth

Antonyms: bumpy, coarse, lumpy, rough, uneven, unsmoothed

Synonym Discussion of PLANE

level, flat, plane, even, smooth mean having a surface without bends, curves, or irregularities. level applies to a horizontal surface that lies on a line parallel with the horizon <the vast prairies are nearly level>. flat applies to a surface devoid of noticeable curvatures, prominences, or depressions <the work surface must be flat>. plane applies to any real or imaginary flat surface in which a straight line between any two points on it lies wholly within that surface <the plane sides of a crystal>. even applies to a surface that is noticeably flat or level or to a line that is observably straight <trim the hedge so it is even>. smooth applies especially to a polished surface free of irregularities <a smooth skating rink>.

⁶plane

verb

planedplan·ing

Definition of PLANE

intransitive verb

a : to fly while keeping the wings motionless

b : to skim across the surface of the water

: to travel by airplane

Origin of PLANE

Middle English, from Middle French planer, from plain level, plain

First Known Use: 15th century

Other Aeronautics/Aerospace Terms

airway, apron, corridor, dirigible, fishtail, flat-hat, vector

PLANES Defined for Kids

¹plane

noun \ˈplān\

Definition of PLANE for Kids

: airplane

: a surface in which if any two points are chosen a straight line joining them lies completely in that surface

: a level of thought, existence, or development <The two stories are not on the same plane.>

: a level or flat surface <a horizontal plane>

²plane

adjective

Definition of PLANE for Kids

: ¹horizontal, flat <a plane surface>

³plane

noun

Definition of PLANE for Kids

: a tool that smooths wood by shaving off thin strips

⁴plane

verb

planedplan·ing

Definition of PLANE for Kids

: to smooth or level off with a tool made for smoothing

: to remove with or as if with a tool for smoothing wood

Medical Dictionary

plane

noun \ˈplān\

Medical Definition of PLANE

a : a surface that contains at least three points not all in a straight line and is such that a line drawn through any two points in it lies wholly in the surface b : an imaginary plane used to identify parts of the body or a part of the skull—see frankfort horizontal plane, midsagittal plane

: a stage in surgical anesthesia <a light plane of anesthesia is maintained with cyclopropane—Journal of the American Medical Association>