I've looked up 'bata', and the RAE says it comes from French. About 'batín' doesn't say anything.
If you finally find out, tell me.
The French source of bata
mentioned by Magg is given by the dictionary of the Real Acadamia as ouate
, the main modern meaning of which is "cotton wool" (US "absorbent cotton"?).
derives from wadda
, a medieval Latin word of uncertain origin but almost certainly connected to German Watte
/ Dutch watten
(cotton wool) and, of course, English wad
(soft material for padding or stuffing),
Old English wadmal
(a type of woollen cloth used for making cheap garments), from Old Norse vaðmal
is likely also to be related.
It would be nice if batt
(cotton or woollen wadding used in quilts, mattresses, etc.), with its similarity to the sound of bata
were also to be a member of the family; alas that word comes from an obsolete word meaning "beaten", the material originally being made by beating fur, wool, etc.
, however, another relation we should not forget to invite to the reunion party. French ouate
has been borrowed into Spanish not just once but a second time, as the word guata
And let's remember little brother too. Batín
is simply a diminutive form of bata