The word "midsummer" refers to the middle of the summer season. It is the time around the summer solstice, when days are longest and nights are shortest. Full definition
The ice found its way into «the drinks of Maharajahs, of men and women in waterfront bars in midsummer in Martinique,» he says, over soft music that mixes in sounds referencing the industry and export geography. (nytimes.com)
Cleanup and construction work will begin by midsummer on the initial phase of the planned Elmwood Crossing redevelopment of the former Women & Children's Hospital site in Elmwood Village, now that the development team has received final city approval for the first building. (nystateofpolitics.com)