ASPA

ASPA may be:American Scholastic Press AssociationAmerican Society for Public AdministrationAotearoa Student Press AssociationASPA (gene), located on the human chromosome 17American Servicemembers' Protection ActAssociation for Scottish Public AffairsAssociation of Singapore Patent Attorneys
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The Aspa was a Czech automobile, a successor to the Stelka, manufactured from 1924 until 1925 at a small machine factory in Pribram. The car used many Ford parts, including a Model T engine. Very few units were built.
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n. cross; multiplication sign; crosspiece; sail; blade

v. wind, be twisted around, twist around; annoy, irritate

n. st. andrew's cross

v. erase, eliminate

= cross, blade, rotor blade, propeller.
Ex: Examples of iconic expressions are the cross and the Crescent representing Christianity and Islam respectively.
Ex: The more blades a helicopter has then the lower the weight that is carried on each.
Ex: The design of helicopter rotor blades presents one of the greatest challenges to flight.
Ex: The propeller on an aircraft converts the turning power of an engine's crankshaft into the thrust force.