さもあらん
Meanings
1
it's probably so; it stands to reason
usually written using kana alone
A somewhat formal or literary expression meaning 'it is likely so' or 'that makes sense'. Often used to acknowledge a plausible statement or situation. Compare with さもありなん, which is more common.
See also: さもありなん
If he says so, it's probably true.
The rumor that those two are getting married seems quite plausible.