adjective
ugly, hideous
A2
hässlich means 'ugly' or 'hideous'. It's a gradable adjective: comparative hässlicher, superlative am hässlichsten. Common antonyms include schön, hübsch, wunderschön. No special prepositions or reflexive use. Regular adjective behavior in comparison and inflection; used before nouns or predicatively with appropriate endings.
Examples
Das Haus ist wirklich hässlich.
The house is really ugly.
Das Gebäude sah hässlich aus, obwohl die Stadtverwaltung versprach, es zu sanieren, sodass die Bewohner unzufrieden blieben.
The building looked ugly even though the city council promised to renovate it, so the residents remained dissatisfied.
Die Kleidung war so hässlich, dass ich sie nicht tragen wollte.
The clothes were so hideous that I didn't want to wear them.
Details
Mnemonics
Imagine a very unpleasant painting and label it 'hässlich'.
Think 'hassle' (häss-) to remember something unpleasant to look at.
Notes
Hässlich is a gradable adjective and can be compared. Use appropriate adjective endings depending on case, gender, and definiteness.