What is considered speech delay at 3?

I think it's tye amount of words they should be able to say by now, and stringing short sentences together instead of just 2 or 3 words.
Plus the forming of the words and if they speak at the back of the throat or more the front of the mouth.

If you're concerned, try talking to your child's doctor or a speech therapist.
Almost 3 year olds will often still have trouble stringing a sentence along and holding a proper conversation but if you're concerned, early intervention is always best! There's also a workshop by this person that's pretty good https://www.instagram.com/raisinglittletalkers?igsh=MTZrd210bGpxd3huYw==