Not Enough, Insufficient, Not Sufficient
expression
You know the word 足りる from Level 4. What is this one? it's the opposite (negative form on a verb is ない). So, what is the opposite of 足りる (To be sufficient)? The opposite is to not be sufficient or not enough.
たりない
The reading is the same as 足りる (たりる) which you should have seen in Level 4.
お金が十円足りないんです。
I’m ten yen short.
玉ねぎが一つ足りない。
We are one onion short.
このソファをロフトに上げるには力が足りない。
I don't have enough strength to raise this sofa to the loft.