In grammar, conditional sentences are “If …, then …” statements. They make a statement that if something happens, then something else will happen.
The ‘if’ clause is referred to as the protasis by grammarians. It comes from the Greek words ‘pro’ (meaning before) and ‘stasis’ (meaning ‘stand’). So, the protasis means ‘what stands before’ or ‘comes first’ as far as these two clauses are concerned. The ‘then’ clause is termed the apodosis; it is what ‘comes after’ the protasis.
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If I accept this explanation of the protasis, then I have to do the same with the apodosis – although being pro-taxis around here means one doesn’t get them in ‘appy doses. They swarm.