downcutv.

Brit.

/ˈdaʊnkʌt/, U.S.

/ˈdaʊnˌkət/

Inflections: Past tense and past participle downcut;

Origin: Formed within English, by derivation. Etymons: down- prefix, cut v.

Etymology: < down- prefix + cut v., after downcutting n.

Geology.

intransitive. Of a river, stream, etc.: to erode downwards so as to deepen its valley or channel. Also transitive: to deepen (a valley or channel) by downward erosion. Cf. downcutting n.

ΚΠ

1903 Bull. Amer. Geogr. Soc. 35 78 Lake-lowering, then, allowed the hanging valleys to be downcut.

1911 Prof. Papers U.S. Geol. Surv. No. 72. 121 The streams have cut to depths of 300 to 500 feet, and most of them are still actively down cutting.

1954 J. F. Kirkaldy Gen. Princ. Geol. xiv. 212 It has been suggested that the depth of the stupendous gorges cut by the River Brahmaputra..is due to the river having had to downcut most vigorously to maintain its path across a block that was being slowly isostatically uplifted.

1989 L. Clayton & J. W. Attig Glacial Lake Wisconsin (Geol. Soc. Amer. Mem. No. 173) 25/2 If no tilting occurred while the outlet was in use, but the outlet was downcut while in use, a series of parallel shorelines should result.

2000 Land & Water Sept. 12/2 Streams generally downcut at the upstream end of a channelization project and aggrade at the downstream end.

This entry has been updated (OED Third Edition, December 2018; most recently modified version published online March 2022).

单词	downcut
释义	downcutv. Brit. /ˈdaʊnkʌt/, U.S. /ˈdaʊnˌkət/ Inflections: Past tense and past participle downcut; Origin: Formed within English, by derivation. Etymons: down- prefix, cut v. Etymology: < down- prefix + cut v., after downcutting n. Geology. intransitive. Of a river, stream, etc.: to erode downwards so as to deepen its valley or channel. Also transitive: to deepen (a valley or channel) by downward erosion. Cf. downcutting n. ΚΠ 1903 Bull. Amer. Geogr. Soc. 35 78 Lake-lowering, then, allowed the hanging valleys to be downcut. 1911 Prof. Papers U.S. Geol. Surv. No. 72. 121 The streams have cut to depths of 300 to 500 feet, and most of them are still actively down cutting. 1954 J. F. Kirkaldy Gen. Princ. Geol. xiv. 212 It has been suggested that the depth of the stupendous gorges cut by the River Brahmaputra..is due to the river having had to downcut most vigorously to maintain its path across a block that was being slowly isostatically uplifted. 1989 L. Clayton & J. W. Attig Glacial Lake Wisconsin (Geol. Soc. Amer. Mem. No. 173) 25/2 If no tilting occurred while the outlet was in use, but the outlet was downcut while in use, a series of parallel shorelines should result. 2000 Land & Water Sept. 12/2 Streams generally downcut at the upstream end of a channelization project and aggrade at the downstream end. This entry has been updated (OED Third Edition, December 2018; most recently modified version published online March 2022). < v.1903
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