Oxford’s online English dictionary has moved to Lexico.com.
Besides the dictionary and thesaurus, there are sections on grammar, spelling, writing, punctuation, word origins, etc.
For example, do you know the longest one-syllable English words? There are several that have nine letters:
- screeched /skriːʧt/
- schlepped /ʃlɛpt/
- scratched /skræʧt/
- scrounged /skraʊnʤd/
- scrunched /skrʌnʧt/
- stretched /strɛʧt/
- straights /streɪts/
- strengths /strɛŋθs/
(Phonetic transcriptions from toPhonetics.)
Oxford Learner’s Dictionaries are still at oxfordlearnersdictionaries.com.