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.
Hysterosalpingography (HSG), also known as uterosalpingography,[1] is a radiologic procedure to investigate the shape of the uterine cavity and the shape and patency of the fallopian tubes. It entails the injection of a radio-opaque material into the cervical canal and usually fluoroscopy with image intensification.