Structured Word Inquiry of 'Sebacic'

What is the morphology of the word sebacic? I encountered this word while studying the related word sebaceous. Sebaceous is borrowed from Latin sēbāceus, which comes from sēbum +‎ –āceus, and is analyzable in Modern English as consisting of two morphemes:

I initially spelled the <Sebe> base with the replaceable <e> because the vowel-initial -aceous, an adjective suffix, replaces the <e> in sebaceous. The vowel-initial Latin suffix -um also replaces the <e> in sebum:

Then, while looking at sebaceous on Wiktionary, I discovered the related term sebacic acid. Sebacic acid is a dicarboxylic acid that is a derivative of castor oil (vegetable oil pressed from castor beans) and originally prepared from tallow. The base <Sebe> denotes “fat, tallow, grease, suet,” which connects to the initial <Seb> in sebacic. But what is the <acic>?

I had two hypotheses. The first was that the <acic> was a modern suffixal coinage from -aceous + -ic:

?<Sebe + acic → sebacic>

The second was that the <ac> in sebacic came from acid. I already knew that the base of acid is <Ac(e)> denoting “sour, sharp, tart, needle” with the parenthetical <e> based on the related word acanthus:

<Ac(e) + id → acid>
<Ac(e) + Anth + us → acanthus>

Thus, if the <acic> of sebacic consisted of <Ac(e) + id>, I needed to amend my initial base from <Sebe> with a replaceable <e> to <Seb(e)> with a parenthetical <e>:

<Seb(e) + aceous → sebaceous>
<Seb(e) + um → sebum>
?<Seb(e) + Ac(e) + ic → sebacic>

The word sebacic could thus consist of the two bound bases <Seb(e)> and <Ac(e)>, both with parenthetical <e>’s, and the adjective suffix -ic.

However, I could not find any evidence that supported the <ac> as being the same <Ac(e)> as in acid. Instead, Merriam-Webster identifies English sebacic as coming from French sébacique, which comes from Latin sebaceus. The French -ique is akin to the English -ic. Thus, unless I find a source that explicitly states that the <ac> in sebacic was coined from acid, then the word consists of the base <Sebe> and the modern suffixal construction -acic.