before vowels log-, word-forming element meaning "speech, word," also "reason," from Greek logos "word, discourse; reason," from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')."

1580s, "the divine Word, second person of the Christian Trinity," from Greek logos "word, speech, statement, discourse," also "a computation, account," also "reason, judgment, understanding," from PIE *log-o-, suffixed form of root *leg- (1) "to collect, gather," with derivatives meaning "to speak," on notion of "to pick out words." The Greek word was used by Neo-Platonists in metaphysical and theological senses involving notions of both "reason" and "word" and subsequently picked up by New Testament writers.

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.

"large saw used for cutting timber, operated by two men, one (the pit-sawyer) standing in the pit below the log that is being sawed, the other (the top-sawyer) standing on the log," 1670s, from pit (n.) + saw (n.1).

"stalk of a plant," 1785, from French stipe, from Latin stipes "log, post, tree trunk" (see stiff (adj.)).

"small lump, butt-end or piece," 1560s, probably cognate with Low German knubbe "knot, knob," Danish knub "block, log, stump" (see knob).

East Indies log raft, 1670s, from Hindi or Malayalam, from Tamil (Dravidian) kattu-maram "tied wood," from kattu "tie, binding" + maram "wood, tree." It also was used in the West Indies and South America.

1883, in architecture, "piece of a wall between two openings," as the central pillar of a great doorway," from French trumeau, literally "calf of the leg" (12c.), from a Germanic source (compare German Trumm "end, stump," Swedish dialectal tromm "stump, end of a log").

"ascertaining of the position of a ship by measurement of the distance run" (without observation of heavenly bodies), 1610s, perhaps from nautical abbreviation ded. ("deduced") in log books, but it also fits dead (adj.) in the sense of "unrelieved, absolute."

"sloping timber of a roof," c. 1200, from Old English ræftras (West Saxon), reftras (Mercian), both plural, "a beam, pole, rafter of a building," related to Old Norse raptr "log," from Proto-Germanic *raf-tra-, from PIE *rap-tro-, from root *rep- "stake, beam."