The state of the tide when the water is at its highest(noun)
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Use "highwater" in a sentence
"She remembers being teased about her "highwater" pants as a kid, but she just can't accept her son's argument that without $100 sneakers, he might be bullied for having uncool shoes."
""Here's where we can play real Robinson Crusoe," Billy cried, as they crossed the hard sand from highwater mark to the edge of the water."
"White Fang (1906) and Before Adam (1907) together constitute the highwater mark of London's blatant use of evolutionary concepts in two tawdry pieces of naturalistic fiction."