Sentence:  The seemingly quiet ocean had crashed a wall of water from 10 to 100 feet <WSD>high</WSD> upon beaches crowded with bathers , drowning thousands of them and flattening villages along the shore . 
Meaning of the word marked with <WSD> tags:  (literal meaning) being at or having a relatively great or specific elevation or upward extension (sometimes used in combinations like `knee-high')