If I don't know the word in English when I'm talking, I'll say "thingy/thing" - until someone corrects me or I settle with a better word.
Ex:
Use that thingy over there to make it work. Uhh...that thing, uh - the button? The port? Whatever it's called. Yeah, that thing.
I have heard from a Venezuelan that they use "vaina". "¿Qué es la vaina...?"
Is there a word like thing/thing in Spanish that is recognized in both Spain and most of Latin America? Something that I can use to keep the convo going in a more native way while not knowing the right word like I do in English? Is it just cosa?
Thank you!
Thing
is more integral in the english language (some-thing; any-thing; is that a thing now?;....), and usage as an interjection as you describe is def. frowned upon and does not convey clarity. For the diminutives and the problems entailed therewith, have a look here: es.wikipedia.org/wiki/Diminutivo . Other than that cosilla or cosita will be understood by many.