"the science of plants," 1690s, from botanic. The -y is from astronomy, etc. Botany Bay in Australia so called by Capt. Cook (1770) on account of the great variety of plants found there; later it was a convict settlement (1778).
late 14c., "pertaining to menses of females," from Old French menstruel and directly from Latin menstrualis "monthly," especially "of or having monthly courses," from menstruus "of a month, every month, monthly, pertaining to a month," from mensis "month" (see moon (n.)). Occasionally, in astronomy, "monthly" (1590s).
early 15c., "a knot or lump," from Latin nodus "knot" (from PIE root *ned- "to bind, tie"). Originally borrowed c. 1400 in Latin form, meaning "lump in the flesh." Meaning "point of intersection" (originally in astronomy, of planetary orbits with the ecliptic) is recorded from 1660s.
1650s, "act of carrying out or away," from Late Latin evectionem (nominative evectio) "a carrying upward, a flight," from Latin evehere, from assimilated form of ex "out of, from within" (see ex-) + vehere "to carry" (from PIE root *wegh- "to go, move, transport in a vehicle"). Astronomy sense, "second lunar inequality," is from 1706.
1620s, "bearing off or away," from French déférent (16c.), from Latin deferentem (nominative deferens), present participle of deferre "to carry down or away" (see defer (v.2)). Earlier in Middle English as a word in Ptolemaic astronomy (early 15c.) to explain the apparent motion of planets.
Old English deorcnysse "absence of light," from dark (adj.) + -ness. The 10c. Anglo-Saxon treatise on astronomy uses þeostrum for "darkness." Figurative use for "sinfulness, wickedness" is from early 14c. From late 14c. as "obscurity," also "secrecy, concealment," also "blindness," physical, mental, or spiritual.
c. 1400, elongacioun, in astronomy, "angular distance of a planet from the sun as it appears from the earth;" early 15c., "extension, spreading," from Medieval Latin elongationem (nominative elongatio), noun of action from past-participle stem of Late Latin elongare "remove to a distance," from assimilated form of Latin ex "out" (see ex-) + longus "long" (see long (adj.)).