foil
UK[fɔɪl]US[fɔɪl]
v
to prevent something bad or someone's plan from succeeding.
n
a very thin sheet of metal, used especially for wrapping food.
n
a light, thin sword with a button on its point, used in the sport of fencing.
Etymology
the verb 'foil,' meaning to frustrate or defeat, entered middle english from old french 'fuler' or 'foiler,' meaning to trample or full cloth, which itself has a probable germanic origin. the noun for thin metal sheet comes from middle english via old french 'foille,' from latin 'folia,' the plural of 'folium' (leaf), reflecting its leaf-like thinness. the fencing term originates in the late 16th century, but its exact path is obscure; it may derive from the verb due to the action of parrying or blunting an attack. these three distinct streams—trampling, a leaf, and a blunted sword—converged in modern english spelling by pure coincidence, creating a true homograph.
Analysis
this word is a simplex form. its modern meanings derive from distinct but convergent historical paths.
Examples
the security forces foiled a planned terrorist attack.
cover the dish with aluminum foil before baking.
she won a silver medal in foil at the national championships.