Indian Evidence Act, 1872
When language use in a documents is plain it itself, but is unmeaning in reference to existing facts, evidence may be given to show that it was in a peculiar sense.
A sells to B, by deed, "my house in Calcutta"
A had no house in Calcutta, but it appears that he had a house at Howrah, of which B had been in possession since the execution of the deed.
These facts may be proved to show that the deed related to the house at Howrah.