This is the 14299th most frequent German word.
hissen
To hoist or raise (e.g., a flag or sail).
This usage of 'hissen' is educational, teaching the correct procedure for hoisting a flag.
Die Schüler lernten, wie man korrekt eine Fahne hisst.
The students learned how to properly raise a flag.
Here, 'hissen' is used in the sense of raising sails, reflecting nautical terminology.
Die Mannschaft hisste die Segel bei starkem Wind.
The crew hoisted the sails in strong wind.
In this sentence, 'hissen' describes the act of raising a flag, a formal or ceremonial usage.