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pyramidal vs. extrapyramidal

[pi-ram-i-dl] / pɪˈræm ɪ dl /

adjective

  1. of, relating to, or shaped like a pyramid.

    the pyramidal form.

  2. of the nature of a pyramid; pyramidlike.

[ek-struh-pi-ram-i-dl] / ˌɛk strə pɪˈræm ɪ dl /

adjective

  1. pertaining to or involving nerve tracts other than the pyramidal tracts, especially the corpus striatum and its associated structures.

  2. located outside the pyramidal tracts.