log-n; 4 Senses

Sense Number 1: segment of a tree trunk

Commentary: LOG[+structure][+component][+segment][+of_trunk][+tree]

What looked like a log in the water was actually an alligator.
The trucks were loaded with logs, headed for the sawmill.
Logs and branches were strewn in the road after the storm.

WordNet 3.0 Sense Numbers: 1

Sense Number 2: the exponent of a base number required to produce a given number

Commentary: LOG[+quantity][+exponent][+required][+by_base_number][+to_produce][+given_number]

The natural log of e is 1.
Find the log of 120 in base 10.
This old math book has log tables listed in the back in Appendix A.

WordNet 3.0 Sense Numbers: 5

Sense Number 3: a record of messages or events

Commentary: LOG[+artifact][+document][+record][+of_events]

Mary kept a log of her body temperature in order to track ovulation times.
The captain recorded their progress and position hourly in the ship's log.
The court has issued subpoenas for the company's email logs.
The operating system keeps several logs automatically on database activities.

WordNet 3.0 Sense Numbers: 2, 3

Sense Number 4: an instrument for measuring the speed of a ship through water

Commentary: LOG[+artifact][+instrument][+measuring][+of_speed][+of_ship]

This float with a knotted line is known as a log and measures a ship's speed by dropping segments of line in the water and measuring the corresponding time.

WordNet 3.0 Sense Numbers: 4