As adverbs the difference between straightaway and promptly
is that straightaway is at once; immediately while promptly is in prompt manner; both soon and quickly.
As a noun straightaway
is a straight section of a racetrack.
As an adjective straightaway
is extending into the distance in a straight line.
straightaway
English
Noun
(
en noun)
A straight section of a racetrack.
Alternative forms
* straightway
Adverb
(-)
At once; immediately.
Alternative forms
* straight away
Adjective
(-)
extending into the distance in a straight line.
promptly
English
Adverb
(
en adverb)
In prompt manner; both soon and quickly.
*
- the ducklings nestled down inside it and promptly fell asleep.