zoology (n.)

also *gweie-, Proto-Indo-European root meaning "to live."

It forms all or part of: abiogenesis; aerobic; amphibian; anaerobic; azo-; azoic; azotemia; bio-; biography; biology; biome; bionics; biopsy; biota; biotic; cenobite; Cenozoic; convivial; couch-grass; epizoic; epizoon; epizootic; macrobiotic; Mesozoic; microbe; Protozoa; protozoic; quick; quicken; quicksand; quicksilver; quiver (v.) "to tremble;" revive; survive; symbiosis; viable; viand; viper; vita; vital; vitamin; victuals; viva; vivace; vivacious; vivarium; vivid; vivify; viviparous; vivisection; whiskey; wyvern; zodiac; Zoe; zoetrope; zoic; zoo-; zoolatry; zoology; zoon; zoophilia; zoophobia; zooplankton.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit jivah "alive, living;" Old Persian *jivaka- "alive," Middle Persian zhiwak "alive;" Greek bios "one's life, course or way of living, lifetime," zoe "animal life, organic life;" Old English cwic, cwicu "living, alive;" Latin vivus "living, alive," vita "life;" Old Church Slavonic zivo "to live;" Lithuanian gyvas "living, alive," gyvata "(eternal) life;" Old Irish bethu "life," bith "age;" Welsh byd "world."

word-forming element meaning "a speaking, discourse, treatise, doctrine, theory, science," from Greek -logia (often via French -logie or Medieval Latin -logia), from -log-, combining form of legein "to speak, tell;" thus, "the character or deportment of one who speaks or treats of (a certain subject);" from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')." Often via Medieval Latin -logia, French -logie. In philology "love of learning; love of words or discourse," apology, doxology, analogy, trilogy, etc., Greek logos "word, speech, statement, discourse" is directly concerned.