A word for not knowing an appropriate word [duplicate]

What is a word to represent a situation in which we feel short of word to be able to express what we want to or what we are feeling .

Solution 1:

I would suggest tongue-tied for want of anything better.

We don't in English have anything quite like the French bon mot, unless we say 'the appropriate word', which is a bit of a mouthful.

Solution 2:

I don't think we have a nice simple word for this!

There are a few common phrases for not being able to find the right word:

• "it's on the tip of my tongue": when the word or phrase may actually come
• "what can I only describe as ...": when you have given up finding the perfect word and just describe what you mean

There is also the word "wordless" or the phrase "words fail me", but these mean "silently" and "I am so upset I cannot really respond" respectively.

If seems a neologism may be required: "word-lost"? :)