In reality some dictionaries don't follow strict alphabetic order. They group related words under a head word. So, for example, with the Royal Institute Dictionary you'll find ใจกลาง, ใจกว้าง, ใจขาด, ใจขุ่น, &c. all listed under ใจ. These secondary entries are listed in strict alphabetical order.
A few dictionaries will list terms which don't start with the head word, but contain it within or at the end. So, for example, เข้าใจ, ใจดี and ดีใจ will all appear under ใจ, and in the order shown (again, strict alphabetical order).
When looking up words, remember that there may be various ways to represent a given sound.
|Sound …||may be written|
|/ay/||ใ◌, ไ◌, ◌ัย|
Words may also be written starting with an unpronounced ห or อ.
Speakers may drop the second consonant of a consonant cluster, so, for example, if you hear kháp you may need to look for khráp, i.e. ครับ and khláp (which doesn't exist).
Conversely, some speakers will hypercorrect, and create a consonant cluster where none exists. For example, กะปอม may be pronounced as if it starts with กระ-. If in doubt, look up both alternatives.
Pronunciation by respelling in Thai usually uses the character ◌ฺ known as พินทุ phinˑthú. It is used to indicate the initial consonant of a consonant cluster. For example, ปลวก is respelled at [ปฺลวก]. ปล is a consonant cluster, so it's pronounced plùak (not *paˑlûak). Similarly, ขรัว is respelled as [ขฺรัว], so we know its pronounced with an initial consonant cluster, khrǔa (not *khaˑrua).
ฝรั่ง is respelled as [ฝะหฺรั่ง]. The second syllable has a pintu under หฺ showing a cluster hr resulting in ร being treated as a high class consonant, so it's faˑràŋ (not *faˑrâŋ).
Common abbreviations include:Parts of speech