1) British slang for a person 2) Hindustani language 3) Worker 
[Arabic] By Allah (Arabic: Wallah, والله) is an Arabic expression meaning `[I promise] by God` used to make a promise or express great credibility on an expression. It is considered a sin among Muslims to use this phrase and follow it up with a lie. Also, some Muslims argue that this is one of the few valid ways of making a promise, th...
• (n.) A black variety of the jaguar; -- called also tapir tiger.
Wal'lah noun (Zoology) A black variety of the jaguar; -- called also tapir tiger . [ Written also walla .] 
Wallah is British slang for a person.
[n] - (India) usually in combination: person in charge of or employed at a particular thing
noun usually in combination: person in charge of or employed at a particular thing; `a kitchen wallah`; `the book wallah`