taffrail log vs patent log

taffrail log and patent log both are nouns.

Word	Noun	Adjective	Verb	Adverb
taffrail log	Yes	No	No	No
patent log	Yes	No	No	No

As nouns, taffrail log and patent log are synonyms defined as:

taffrail log and patent log: a cigar-shaped log with rotary fins that measure the ship's speed

Other synonyms of taffrail log include screw log.

taffrail log (noun)	patent log (noun)
a cigar-shaped log with rotary fins that measure the ship's speed	a cigar-shaped log with rotary fins that measure the ship's speed