I.on [Brit ɒn, Am ɑn, ɔn]PREPWhen on is used as a straightforward preposition expressing position ( on the beach, on the table) it is generally translated by sur: sur la plage, sur la table; on it is translated by dessus: there's a table over there, put the key on it = il y a une table là-bas, mets la clé dessus. on is often used in verb combinations in English ( depend on, rely on, cotton on etc.). For translations, consult the appropriate verb entry ( depend, rely, cotton on etc.). If you have doubts about how to translate a phrase or expression beginning with on ( on demand, on impulse, on top etc.) consult the appropriate noun or other entry ( demand, impulse, top etc.). This dictionary contains usage notes on such topics as dates, islands, rivers etc. Many of these use the preposition on. For the index to these notes . For examples of the above and further uses of on, see the entry below.