Our profession ethics takes us teachers of languages, either secondary or foreign ones to improve those target languages in us, English in my case.
I cannot lie to my students or intend to mean that that is the right word in such or such context, without checking it up.
Something we can do is tell our students next day I shall tell them what the correct word was, in that context.
We teachers ought to be, better said, should be upright and honest. The students, unaware-like, perceive our trying to do our best, though this can be a bit hard for us teachers.
Otherwise we could look up a given word in the classroom dictionary itself, or in an online one; I would recommend you Wordreference: awesome! It’s pretty good. It’s the one I utilize. / Photo from: www nydailynews com. the pic is just an illustration