Borrowed from Latin aculeus.
aculeous (comparative more aculeous, superlative most aculeous)
- (obsolete, rare) Pertaining to a needle.
- 1658, Sir Thomas Browne, The Garden of Cyrus (Folio Society 2007, p. 180)
- And such an order is observed in the aculeous prickly plantation, upon the heads of several common thistles.