"the study of cetaceous animals," 1815, from combining form of Cetacea + -logy. Related: Cetologist.
Entries linking to cetology
Cetacea n.
order of marine mammals including whales, 1795, Modern Latin, from Latin cetus "any large sea creature" (whales, seals, dolphins), from Greek kētos "a whale, a sea monster," which is of unknown origin, + -acea.
-logy
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.