Thailand's own multi-source dictionary — what Thai people actually look words up in.
Details
Longdo aggregates several dictionaries at once (including NECTEC's LEXiTRON and Thai–Thai sources), so a single search shows technical, colloquial and formal senses side by side. Because it is built for Thai users it covers vocabulary that learner dictionaries omit entirely, which matters once you are reading real material. The interface is cluttered and largely in Thai, so it suits intermediate learners more than day-one beginners.