Trichocentrum, Lophiaris, oncidium ??
 

This one finally bloomed after almost a year. Got it from a friend.

How to properly name it?

I think it is a cosymbephorum but i have my doubts with some pictures i've seen on the net of andreanum.

What do you think?

Trichocentrum cosymbephorum does seem to be the most likely possibility.

Really beautiful! Would you mind posting photos of plant and leaves?

Here is a picture of the whole plant. It is the one in the middle.

Leaves are aprox 20-25 cm long

Thank you!

An oncidium in that color is pretty amazing... great growing!

Here is a picture of my Oncidium with the tag. It looks very similar to yours except mine is a tiny baby. Maybe it will help with I'd.

this genus was divided in a work done by William Cetzal and German Carnevalli.
Attachment 124188

A: is Cohniella
B: lophiarella (note large pbulb), they are from central america and Mexico.
C: lophiaris (americas)
D: Trichocentrum

the work separates it in a way that even without flowers you could put it in the right genus. you can either use the old method of calling all of them trichocentrum, or you can go and name your plants as suggested by Cetzal/Carnevalli

both ways are ok.

all trichos that looks like rat tails are cohniella.
all trichos that has a prominent pbulb are lophiarella,
all trichos that has ear mule, but a very small Pbulb are lophiaris.
all trichos that sports very few flowers (some large) or nectaries, keeps the name trichocentrum.

use the picture as reference.

Looks like c to me, as does the OP's.

Dolly, these don't do well staying wet for long. Be careful watering in that big pot. I have a T. tigrinum on a small mount. It has very few roots, but last summer it grew a single new leaf 50% bigger than the previous ones.