adverb
especially, particularly
A2
besonders: adverb meaning especially/particularly; emphasizes degree, used before adjectives or clauses. No reflexivity or auxiliary. Can also mean 'specially' as in 'especially designed.' It's neutral style, common in spoken and written German. No irregular forms; comparative/superlative not applicable to adverbs.
Examples
Das Konzert war toll, besonders das letzte Lied.
The concert was great, particularly the final song.
Ich mag Schokolade, aber dunkle Bitterschokolade besonders.
I like chocolate, but dark chocolate especially.
Der Tag war besonders kalt, sodass viele Schüler früher nach Hause gingen.
The day was especially cold, so many students went home earlier.
Details
Mnemonics
picture a spotlight on one thing that is 'besonders' = stands out from the rest
sounds like 'best on dose' — imagine emphasizing the 'best' dose, i.e., especially good
Notes
Used to emphasize a part or quality. Often appears before the phrase it highlights.