Origin: Latin prefix pre-
Preferably has 2 different meanings across 1 category:
more readily or willingly
"clean it well, preferably with warm water"
"I'd rather be in Philadelphia"
"I'd sooner die than give up"
In preference; by choice; in a preferable manner.
"We would love to visit the museum, but if we must choose another activity, it is preferably an outdoor park walk."
In plain English: Preferably means something is better than other choices, so you should aim for it if possible.
"Please bring your own lunch, but preferably something from home."
Usage: Use preferably to indicate that one option is chosen over another, often appearing after the main verb or at the end of a sentence rather than before it like preferred would be used as an adjective. It signals a strong suggestion without being as forceful as must or should when expressing ideal conditions.
The word preferably comes from combining the adjective preferable with the suffix -ly to form an adverb. It entered English by adding a common grammatical ending to indicate that something is done in a preferred manner.