CIOPW is a collection of artwork by E. E. Cummings published in 1931. The title is an acronym made from the initial letters of the five media Cummings used to produce the collection: charcoal, ink, oil, pencil, and watercolours. Images at http://faculty.gvsu.edu/websterm/cummings/CIOPW/CIOPW.html.
CIOPW contains 99 works, 27 of which are drawings and 72 of which are paintings. Since it is Cummings’ art and not his words that are on display, the title is also to be read as the ancient Greek word σιωπῶ, “I am silent,” with (i) a so-called lunate sigma, (ii) an omicron rather than an omega the first time (a combination sometimes found on Greek inscriptions), (iii) a “P” rather than a “Π” to keep the sound the same, and (iii) a “W” to represent “ω” visually. The title should thus be pronounced “siôpô,” with the stress on the last syllable. Compare his other Greek titles EIMI = εἰμί, “I am”; and XAIPE = χαῖρε (pronounced "chaire," with a guttural ch), "greetings, be well."