layby vs pull-off

layby and pull-off both are nouns.

Word	Noun	Adjective	Verb	Adverb
layby	Yes	No	No	No
pull-off	Yes	No	No	No

As nouns, layby and pull-off are synonyms defined as:

layby and pull-off: designated paved area beside a main road where cars can stop temporarily

Other synonyms of layby include lay-by, rest area, rest stop.

layby (noun)	pull-off (noun)
designated paved area beside a main road where cars can stop temporarily	designated paved area beside a main road where cars can stop temporarily