Elongated, dead water-conducting cells in plants with tapered ends and thick, lignified walls containing pits for water movement. They are the primary water-transporting elements in gymnosperms and provide both conduction and structural support.
From Greek 'tracheia' meaning 'rough artery' (referring to the windpipe) and the suffix '-id' meaning 'resembling.' The term was coined in the 1860s when botanists noticed these cells resembled the rough, ringed structure of animal windpipes.
Tracheids are like drinking straws that died and became super-straws! They stack end-to-end like tiny pipes, but water has to seep through pits in their walls to move up - it's less efficient than vessel elements but way more common in the plant world.
Complete word intelligence in one call. Free tier — 50 lookups/day.