sinistrorse

UK: /ˈsɪnɪˌstrɔːs/, /ˌsɪnɪˈstrɔːs/

US: (sin′ə strôrs′, si nis′trôrs, sin′ə strôrs′)

WordReference Random House Unabridged Dictionary of American English © 2026

sin•is•trorse  (sin′ə strôrs′, si nis′trôrs, sin′ə strôrs′), adj. [Bot.]

1. Botany (from a point of view at the center of the spiral) rising spirally in a counterclockwise manner, as a stem (opposed to dextrorse).

• Latin sinistrōrsus literally, turned leftwards, contraction of *sinistriversus. See sinister, versus
• 1855–60;

sin•is•trorse•ly  (sin′ə strôrs′lē, sin′ə strôrs′-), adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

sinistrorse / ˈsɪnɪˌstrɔːs ˌsɪnɪˈstrɔːs/ adjective

1. (of some climbing plants) growing upwards in a spiral from right to left, or clockwise
   Compare dextrorse

Etymology: 19th Century: from Latin sinistrōrsus turned towards the left, from sinister on the left + vertere to turn

ˌsinisˈtrorsal adjective