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scale 1 (skāl)
a. One of the many small hard dermal or epidermal structures that characteristically form the external covering of fishes and reptiles and certain mammals, such as pangolins.
b. A similar part in other animals, such as one of the thin flat overlapping structures that cover the wings of butterflies and moths.
2. A small, thin, often flattened plant structure, such as one of the modified leaves that cover a tree bud or one of the structures that bear the reproductive organs on the cones of a conifer.
a. A dry thin flake of epidermis shed from the skin.
b. A skin lesion or lesions marked by such flakes.
a. A scale insect.
b. A plant disease or infestation caused by scale insects.
a. A flaky oxide film formed on a metal, as on iron, that has been heated to high temperatures.
b. A flake of rust.
6. A hard mineral coating that forms on the inside surface of boilers, kettles, and other containers in which water is repeatedly heated.
v. scaled, scal·ing, scales
1. To clear or strip of scale or scales: Scale and clean the fish.
2. To remove in layers or scales: scaled off the old paint.
3. To cover with scales; encrust.
4. To throw or propel (a thin flat object) through the air or along a surface, such as water or ice.
5. Dentistry To remove (tartar) from tooth surfaces with a pointed instrument.
6. Australian
a. To cheat; swindle.
b. To ride on (a tram, for example) without paying the fare.
1. To come off in scales or layers; flake.
2. To become encrusted.

[Middle English, from Old French escale, husk, shell, influenced in meaning by Old French escaille, scale of a fish or reptile (both of Germanic origin; see skel-1 in the Appendix of Indo-European roots).]

scalelike adj.
(click for a larger image)
cone of a white pine

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
scale 2 (skāl)
a. A system of ordered marks at fixed intervals used as a reference standard in measurement: a ruler whose scale is in inches.
b. An instrument or device bearing such marks.
c. A standard of measurement or judgment; a criterion.
a. A proportion used in determining the dimensional relationship of a representation to that which it represents: a world map with a scale of 1:4,560,000.
b. A calibrated line, as on a map or an architectural plan, indicating such a proportion.
c. Proper proportion: a house that seemed out of scale with its surroundings.
3. A progressive classification, as of size, amount, importance, or rank: judging divers' performances on a scale of 1 to 10.
4. A relative level or degree: entertained on a lavish scale.
5. A minimum wage fixed by contract: musicians playing a benefit concert for scale.
6. Mathematics A system of notation in which the values of numerical expressions are determined by their places relative to the chosen base of the system: the decimal scale.
7. Music An ascending or descending collection of pitches proceeding by a specified scheme of intervals.
v. scaled, scal·ing, scales
1. To climb up or over; ascend: scaled the peak.
2. To make in accord with a particular proportion or scale: Scale the model to be one tenth of actual size.
3. To alter according to a standard or by degrees; adjust in calculated amounts: scaled down their demands; scaled back the scheduled pay increase.
4. To estimate or measure the quantity of lumber in (logs or uncut trees).
1. To climb; ascend.
2. To rise in steps or stages.

[Middle English, from Latin scālae, ladder; see skand- in the Appendix of Indo-European roots.]

scala·ble adj.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
scale 3 (skāl)
1. An instrument or machine for weighing.
a. often scales See balance.
b. Either of the pans, trays, or dishes of a balance.
v. scaled, scal·ing, scales
To weigh with a scale.
To have a given weight, as determined by a scale: cargo that scales 11 tons.

[Middle English, bowl, balance, from Old Norse skāl; see skel-1 in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

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