This is the 11302nd most frequent German word.
sommer
"Sommer" means "summer" in English.
Here, 'Sommer' is used as the subject and refers to the season known for warm weather.
Der Sommer ist warm und sonnig.
The summer is warm and sunny.
In this sentence, 'Sommer' is used in a prepositional phrase ('im Sommer') to specify the time frame of an action.
Im Sommer gehe ich oft an den Strand.
In the summer, I often go to the beach.
Here, 'Sommer' is part of a compound noun ('Sommerkleid') that describes a type of clothing typical for the summer season.