In Act 3 Scene 3 Lines 300 to 450 of Othello, Shakespeare uses many figures of speech. Figures of speech are words or phrases that have figurative meanings instead of literal meanings. For example, "that ripe tomato is red" is a statement that has a literal meaning: that ripe tomato really is red. On the other hand, "that marathon rummer is a red ripe tomato" is a statement that has figurative meaning: that runner only looks red like a ripe red tomato; the runner is not a tomato. Imagery is another term for figures of speech, but imagery may also be used for purely descriptive passages: for example, "The gentle wind blew the starched yellow curtains with their rows of violet embroidery in a slow, uneven motion."
There are several kinds of literary figures of speech. Some common ones in Shakespeare are metaphor, simile, hyperbole, personification, idioms and puns. In this passage of Othello, Shakespeare uses several of these. For instance, in Line 304 Shakespeare employs two idioms, the meanings of which are lost to contemporary speakers: "whistle her off and let her down the wind." An idiom is a word or set of words that mean something other than their literal meaning: "I'll shop till I drop!" This current idiom doesn't mean you will collapse but that you will shop a lot and enjoy every minute of it!
Line 374 has the metaphor "Dangerous conceits are, in their natures, poisons." A metaphor is a comparison of things that are not alike, in this case the things that are not alike are conceits and poisons. A metaphor does not use the words as, like or than. These words are used in the comparison called a simile: A simile is a comparison of things that are not alike and the comparison is made by using the words as, like or than. Shakespeare's writing is as rich as it is in part because of the abundance of figures of speech that he employs.