Baptizo (Matt 28:18 Trinity A)
Not to be confused with bapto. The clearest example that shows the meaning of baptizo is a text from the Greek poet and physician Nicander, who lived about 200 B.C. It is a recipe for making pickles and is helpful because it uses both words. Nicander says that in order to make a pickle, the vegetable should first be 'dipped' (bapto) into boiling water and then 'baptised' (baptizo) in the vinegar solution. Both verbs concern the immersing of vegetables in a solution. But the first is temporary. The second, the act of baptising the vegetable, produces a permanent change.
When used in the New Testament, this word more often refers to our union and identification with Christ than to our water baptism. e.g. Mark 16:16. 'He that believes and is baptised shall be saved'. Christ is saying that mere intellectual assent is not enough. There must be a union with him, a real change, like the vegetable to the pickle!
Bible Study Magazine, James Montgomery Boice, May 1989. (Cited from the Online Bible)
What does it mean to be permanently immersed in the Triune Name?