Sentence:  I have more than once sat cross-legged in the grass through a long <WSD>summer</WSD> morning and watched without touching while a poppy bud higher than my head slowly but visibly pushed off its cap , unfolded , and shook out like a banner in the sun its flaming vermilion petals . 
Meaning of the word marked with <WSD> tags:  the warmest season of the year; in the northern hemisphere it extends from the summer solstice to the autumnal equinox