put it mildly

Understate, say without exaggeration, as in It's a fairly long way to walk, to put it mildly-twenty miles or so. [First half of 1900s]

Name	Pronounced	Usage
Ermenegilde	-	French
Nina	['ni:nə]
İRfan	-	Turkish
Adamu	-	Old Church Slavic
Maura (1)	MOW-rah (Italian, Spanish)	Italian, Spanish, Late Roman
Zoticus	-	Ancient Greek (Latinized)