As permitted by law; not contrary to law.
"You can legally park here during the day because there are no restrictions on street parking at this time."
In plain English: Legally means something is allowed by the rules of law and approved by judges.
"You can legally drive once you turn sixteen."
Usage: Use legally when describing actions that comply with the rules of a specific jurisdiction, such as stating an act is done legally in this country but illegally elsewhere. This term often contrasts informally with "illegally" rather than requiring formal synonyms like "lawfully."
Legally comes from combining the word legal with the suffix -ly to mean "in a lawful manner." It entered English as a distinct form alongside related words like leally and loyally, which were alternative spellings for similar adverbs at the time.