The term 'explosion noise' can be described by three words: BAM (3 letters), BANG (4 letters), and BLAM (4 letters). BAM is a sharp, loud sound that is often used to describe the sound of an explosion. BANG is a louder, more intense sound that is usually associated with a larger explosion. BLAM is a sound that is similar to BANG but is slightly softer and less intense. All three words are commonly used to describe the sound of an explosion.