[ap-ruh-poh] 
| 1. | fitting; at the right time; to the purpose; opportunely. |
| 2. | Obsolete. by the way. |
| 3. | opportune; pertinent: apropos remarks. |
| 4. | apropos of, with reference to; in respect or regard to: apropos of the preceding statement. |
| apropos of prep. With reference to; speaking of: a funny story apropos of politics. |
apropos of
Concerning, in connection with, as in Apropos of keeping in touch, I haven't heard from her in months. This idiom was a borrowing of the French à propos de ("to the purpose of") in the 17th century. At first it was used without of and meant "fitting" or "opportune," as in Their prompt arrival was very appropos. By the 1700s it was also being used with of, as in the current idiom, for "concerning" or "by way of."
rəˈpoʊ