I have tried googling the correct anatomical terms for commonly shaped jigsaw pieces but can't find any. So either there are none, or they do exist but are not shared outside some secret jigsaw builders society- you know like Freemasonary or Mormonism- but for jigsaws.
Anyway, in order to benefit the amateur jigsaw building world and avoid further references to protrusions, boy bits and nubbins, I offer some clarification on shape names. The simple descriptions below can be extended by adding 'portrait' or 'landscape' as needed, with reference to surface pattern.
OK? Right, we have:
1 tab
2 tab even
2 tab uneven
3 tab
4 tab
Self explanatory, yes? Adopt this terminology today and avoid inappropriate social exchanges, usually tempered by a child belonging to one of you walking into the room asking 'Why are you laughing... again?'
And never again choke and squirt wine out your nose upon hearing the phrase 'None of my nubbins fit in there.'