knapweed
UK[ˈnæpwiːd]US[ˈnæpwiːd]
n
a plant of the daisy family with tough stems and purple thistle-like flower heads.
n
any of several related plants, especially of the genus centaurea.
Morpheme Breakdown
knap
weed
knap
weed
Etymology
the word 'knapweed' is a compound formed from two old english elements. the first part, 'knap', originally meant a small rounded protuberance or a button, which was applied to the distinctive hard, knob-like flower head of this plant. the second part, 'weed', is a generic term for a wild plant or herb. the compound thus literally describes a 'wild plant with a knob-like head', a direct reference to its most conspicuous physical feature. this descriptive naming pattern is common in english for wildflowers, where a prominent characteristic is used to distinguish the species.
Analysis
Structure: knap + weed
knap (middle english, from old english cnæp, meaning 'knob' or 'button', referring to the plant's flower head). weed (old english wēod, meaning 'herb', 'plant', or specifically 'wild plant').
Examples
the field was dotted with the purple blooms of common knapweed.
butterflies are often seen feeding on the nectar of knapweed.
farmers sometimes consider knapweed an invasive weed in pastures.