1. Unexpectedly sudden: an abrupt change in the weather.
2. Surprisingly curt; brusque: an abrupt answer made in anger.
3. Touching on one subject after another with sudden transitions: abrupt prose.
4. Steeply inclined. See Synonyms at steep1.
5. Botany Terminating suddenly rather than gradually; truncate: an abrupt leaf.
[Latin abruptus, past participle of abrumpere, to break off : ab-, away; see AB-1 + rumpere, to break; see reup- in the Appendix of Indo-European roots.]
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