large or extensive in breadth or importance or comprehensiveness; "the might have repercussions of unimaginable largeness"; "the very extensiveness of his power was a temptation to abuse it"
a forceful forward rush or flow; "from the bow she stared at the mesmerising onrush of the sea where it split and foamed"; "the explosion interrupted the wild onrush of her thoughts"
the warmest season of the year; in the northern hemisphere it extends from the summer solstice to the autumnal equinox; "they spent a lazy summer at the shore"