Within Hebrew texts, here and there some difficult words appear. It often happens that... we find no way to discover what they are, what they mean.
Of course, a difficult word we do not know can be a person's name, a city name, a nickname, a particular name: the same occurs in every language.
But it is quite true that Oham can here help us in this approaching to what a given difficult word is.
Let us suppose we find the word ילילו within one of the Kinot contained in an early 14th century handwritten document (1)
The first part of the sentence is: ...בליל זה יבכיון וילילו בניי
The third word is found in the Bible: Isa 33:7 (last word in the verse)
The sentence means: In this night my sons will weep and xxx.
The xxx, word ילילו, becomes a stone in the way. Not because of the initial waw, that is surely the copulative conjunction meaning "and", but because of ילילו.
This seems a difficult word. Of course we'll not find it in the Dictionary.
(1) See Catalogue of the Hebrew Manuscripts in the Vatican Library, Vat. ebr. 319 (on page 260 - First edition, 2008)