polttopiste

== Finnish == === Etymology === poltto (“burn, burning”) +‎ piste (“point”), from the fact that a convex lens concentrates the rays of the sun into the focus of the lens, which may cause a flammable material to catch fire. === Pronunciation === IPA(key): /ˈpoltːoˌpisteˣ/, [ˈpo̞l̪t̪ːo̞ˌpis̠te̞(ʔ)] Rhymes: -iste Syllabification(key): polt‧to‧pis‧te Hyphenation(key): poltto‧piste === Noun === polttopiste (optics) focus, focal point (point at which reflected or refracted rays of light converge) Synonym: fokus (mathematics) focus (point of a conic at which rays reflected from a curve or surface converge) ==== Declension ==== ==== Derived terms ==== === Further reading === “polttopiste”, in Kielitoimiston sanakirja [Dictionary of Contemporary Finnish]‎[1] (in Finnish) (online dictionary, continuously updated), Kotimaisten kielten keskuksen verkkojulkaisuja 35, Helsinki: Kotimaisten kielten tutkimuskeskus (Institute for the Languages of Finland), 2004–, retrieved 3 July 2023