IHS

Proper noun

 * 1)   a US health agency
 * , the Greek form of Jesus.
 * 1)   a US health agency
 * , the Greek form of Jesus.

Etymology
The reference to Jesus is from the first three letters of Jesus' name in, , arising perhaps circa 14th century. The interpretation as an abbreviation is apparently a later back-formation when the Greek was no longer remembered. (See wikipedia Christogram.)

Phrase

 * 1) In hoc signo (In this sign). Commonly seen on Christian churches.