n. pl. ac·cliv·i·ties An upward slope, as of a hill. [Latin acclīvitās, from acclīvis, uphill : ad-, ad- + clīvus, slope; see klei- in the Appendix of Indo-European roots.] ac·clivi·tous (-ĭ-təs) adj. |
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.