dissimulate = dissemble

[panicmonger]

I would just like to know whether there is such words as "dissimulate", "altercate" & "deflagrate".

Are they only used in the U.S.A because there are no such words in UK dictionaries?

By the way, can I use "very much involved" in my writings?
For example: I'm very much involved in politics.

Thank you so much.

[5jj]

I would just like to know whether there is such words as "dissimulate", "altercate" & "deflagrate".

Are they only used in the U.S.A because there are no such words in UK dictionaries?

By the way, can I use "very much involved" in my writings?
For example: I'm very much involved in politics.

Thank you so much.

The Oxford Concise lists all three, the Oxford Advanced Learner's only the first.