verb
to act, to trade
B1
Handeln means 'to act' (take action) or 'to trade/negotiate'. It's a regular weak verb using haben in perfect forms (hat gehandelt). Non-reflexive. Note a common sense 'be about' uses handeln von + Dative, while 'trade' often appears as handeln mit jemandem. Also used as noun 'Handeln'.
Examples
In gefährlichen Situationen handelt sie sehr schnell.
In dangerous situations she acts very quickly.
Er handelte klug.
He acted wisely.
Der Anwalt handelte entschlossen, damit die Klage fristgerecht eingereicht wurde.
The lawyer acted decisively so that the lawsuit would be filed on time.
Details
Mnemonics
picture someone handling a situation (acts) or negotiating trades across a table
sounds like English 'handle' — acting/handling a situation
Notes
Can mean 'to act/behave' or 'to trade/deal in' depending on context. Commonly used both transitively and intransitively.