In context of readings (not rules/terms):
Qalqalah (“bouncing”, don’t teach term),
Ghunna (nasal sound)
Note that Jannah in English includes a nun with shaddah, and therefore has two counts of nasalization, which indicates emphasis. It’s also interesting to note that in terms of the meaning above for different words for “garden,” Jannah is also special in that it indicaes two things, which are its “lushness” and “largeness”.
When reading “Bustan”, the sin is significant in that there is a “whispering” sound that spreads because of the sukun. Here, the bustan is also large and spread.
You will often see that there is a connection sound and meaning.