21-letter words containing a, n, g, l, i, c
- polarizing microscope — a microscope that utilizes polarized light to reveal detail in an object, used especially to study crystalline and fibrous structures.
- polygenic inheritance — the heredity of complex characters that are determined by a large number of genes, each one usually having a relatively small effect.
- reconnaissance flight — a flight made by an aircraft in order to obtain military information about a particular place
- replacement algorithm — The method used to determine which entry in an associative cache to flush to main memory when it is desired to cache a new block of data. The "least recently used" algorithm flushed the block which has not been accessed for the longest time. A random replacement algorithm picks any block with equal probability.
- schlieren photography — a type of photography which records schlieren
- simple actor language — (language) (SAL) A minimal actor language, used for teaching in:
- siren call/siren song — A siren call or siren song is the appeal that something has although it is harmful or dangerous.
- social anthropologist — an anthropologist who deals with cultural and social phenomena such as kinship systems or beliefs, esp of nonliterate peoples
- stained glass ceiling — a situation in a church organization in which promotion for a female member of the clergy appears to be possible, but discrimination prevents it
- submerged arc welding — a type of heavy electric-arc welding using mechanically fed bare wire with the arc submerged in powdered flux to keep out oxygen
- supergranulation cell — one of a number of large convection cells in the photosphere and chromosphere of the sun, each having a diameter of 10,000–20,000 miles (16,000–32,000 km) and lasting longer than a day.
- teleological argument — the argument purporting to prove the existence of God from empirical facts, the premise being that the universe shows evidence of order and hence design
- to kill a mockingbird — a novel (1960) by Harper Lee.
- topological invariant — a property of a topological space that is a property of every space related to the given space by a homeomorphism.
- tubercular meningitis — an infection of the membranes of the central nervous system caused by the bacterium Mycobacterium tuberculosis; features can include fever, headache, and coma
- undesirable discharge — a discharge under other than honorable conditions of a person from military service by administrative action.
- vertically challenged — short in stature.
- virginia (rail) fence — a zigzag fence made of rails laid across one another at the ends