Is it acceptable to substitute the word "Definitely" with the word "Defo"?

[flobadob]

And are there other acceptable shortened words?

[MichaelZZ]

Yes, of course it is, if you are talking to your friends.
No, of course it isn't, if you are in a formal situation or with someone whom you do not know.

[grasscarp]

Why would you want to shorten it. If you want two syllables instead of four, why not say "for sure"

[sandyRoe]

It might become acceptable in time. Pram was once perambulator and prom was promenade.

[con-amca]

If I said "defo" to my friends when I meant "definitely", they wouldn't know what
I was talking about.

[factor-fiction]

"Yes" is even shorter

[factor-fiction]

Does anyone shorten 'absolutely' to 'abso'?

[sunny-dave]

n

[MarkRae]

I blame Jimmy Young...

[grasscarp]

And if you can't be bothered to open your mouth nod your head.

[grasscarp]

I am ashamed to say I went out a couple of times with jy around 1970.

[Prudie]

Uni seems to be an almost acceptable shortening now. I even use it myself although it grated on me for ages.

[boxtops]

I find myself saying IMO in conversation lately, such is the influence of Answerbank.

[grasscarp]

When my girls were up north at uni they talked about going to the offy which I had not heard before.

[Prudie]

I find myself putting PMSL in work e-mails

[WyeDyed]

Goodbye is a corruption of "God be with ye"

Personally I don't like defo or dis but our wonderful language is, and always will be, a work in progress.

[jake-the-peg]

It starts with rare use then moves to interchangeable like

'Plane - aeroplane
'phone - telephone

Then the full word becomes rarer to the point that it's archaic

'Bus - Omnibus

But lots of slang dies a death and is never seen again

don't quite see "defo" making the cut but what do I know

[flobadob]

Aw fo sho.

[heathfield]

Fab?