Definition of Quatrain. A poem, unit or stanza of four lines of verse, usually with a rhyme scheme of abab or its variant, xbybâ. âThe rhyming fourâline groups that make up the first eight or twelve lines of a sonnet are also known as quatrainsâ.
HSPF (Heating Seasonal Performance Factor) is a term used in the heating and cooling industry.HSPF is specifically used to measure the efficiency of air source heat pumps.he higher the HSPF rating of a unit, the more energy efficient it is. HSPF is a ratio of BTU heat output over the heating season to watt-hours of electricity used. It has units of BTU/watt-hr. Depending on the system, an HSPF â¥ 8 can be considered high efficiency and worthy of a US Energy Tax Credit.
Hereditary spastic paraplegia (HSP), also called familial spastic paraparesis (FSP), refers to a group of inherited disorders that are characterized by progressive weakness and spasticity (stiffness) of the legs.Early in the disease course, there may be mild gait difficulties and stiffness.ereditary spastic paraplegia (HSP), also called familial spastic paraparesis (FSP), refers to a group of inherited disorders that are characterized by progressive weakness and spasticity (stiffness) of the legs.