Original thread: [1]

Question: How do you refer to っ in spoken Japanese? (i.e. What do I call the little つ?)

Answer

1. A quick answer: 小さいつ.
2. A "fancier" definition: 促音.

A longer explanation

• 小さい「つ」 refers to the character っ, while 促音 refers to the phoneme; the difference is however negligible.
• In the same way that 撥音 refers specifically to ん, 促音 also refers specifically to っ.
• Sometimes, つまる音（おと） is used instead of 促音, and はねる音 is used instead of 撥音; but these are quite obscure usages.