AVG 2.9

Chapter 2 (The Seekers Joy at Self-Cognizance): Verse 9
अहो विकल्पितं विश्वमज्ञानान्मयि भासते ।
रूप्यं शुक्तौ फणी रज्जौ वारि सूर्यकरे यथा ॥ २-९॥

PURPORT:
Oh!, the universe appears within me
from incomprehension, just as
silver appears within nacre, as
a snake appears within coiled rope,
and a mirage appears at the bright horizon.

TRANSLITERATION:
अहो विकल्पितम् विश्वम् अज्ञानात् मयि भासते ।
aho vikalpitam viśvam ajñānāt mayi bhāsate ।
रूप्यम् शुक्तौ फणी रज्जौ वारि सूर्यकरे यथा ॥ २-९॥
rūpyam śuktau phaṇī rajjau vāri sūryakare yathā ॥ 2-9॥

MEANING:
aho (अहो) = oh wow! [an exclamation of being pleasantly surprised]
vikalpitam (विकल्पितम्) = imagined/fancied/conjectured
viśvam (विश्वम्) = universe
ajñānāt (अज्ञानात्) = through ignorance/from incomprehension
mayi (मयि) = in me/within me
bhāsate (भासते) = appears/to be conceived or imagined ।
rūpyam (रूप्यम्) = wrought silver or gold
śuktau (शुक्तौ) = within the nacre (nacre is an organic-inorganic composite material produced by some mollusks as an inner shell layer)/within the mother of pearl
phaṇī (फणी) = snake/serpent
rajjau (रज्जौ) = within a rope [as in mistaking the form of a snake within the shape of coiled rope]
vāri (वारि) = water/fluid [reference to mirage like water is the intent here]
sūryakare (सूर्यकरे) = in the sunbeam/in the rays of the sun [reference to the bright horizon of a desert where one might run into a mirage is the intent here]
yathā (यथा) =  just as/as ॥ 2-9॥

COMMENTS:
All of reality is interaction. Interaction that manifests as reality is the mechanism whereby dependent processes act in concert and conjunction to give rise to emergent phenomena that may themselves serve as the causal conditions for the arising of still others. Phenomena at the smallest scales (quarks) to the biggest scales (superclusters of galaxies) are manifested in a similar manner. Sentient beings like ourselves see patterns and entities within such dependent interactions and label (assign name and form) them accordingly. In addition to seeing the patterns, we are also conditioned to seeing connections and causal relations between such patterns (regardless of whether such causal relations exist or not) and our immediate tendency is to name and label such connections.
Over time, our collective selves become more and more attuned and accustomed to labeling and naming and we tend to lose semblance of the underlying reality. The labels, heuristics, names and shortcuts that were supposed to aid us in getting to the nature of the underlying reality now becomes an illusionary reality overlaid on the underlying reality.
It is important at this juncture to clearly understand that the world and the universe is not an illusion. Many of us are caught up in this semantic turn of phrase and then tend to discount conversations that involve the words 'world' and 'illusion' in one sentence. The world and universe is NOT an illusion. The world and the universe is LIKE an illusion. This is what the verses also eloquently state here ("silver appears within nacre, snake appears within coiled rope, and a mirage appears at the bright horizon").
The illusion engendered can be clarified by a spiritual-scientific discipline combined with concentrative awareness and contemplative reflection. Understand that world and the universe being LIKE an illusion is primarily due to two fundamental reasons:  our conditioning and cognitive biases in not seeing things the way they are in truth and secondly, the process of 'thinking' itself taking a primal position as light of consciousness crowding out the underlying awareness rooted within oneself.
As a final note, there is a word 'maya' in Sanskrit that beautifully describes this the concept of illusion: Maya (माया / māyā), literally "illusion" or "magic", has multiple meanings in Indian philosophies depending on the context. In ancient Vedic literature, Māyā literally implies extraordinary power and wisdom. In later Vedic texts and modern literature dedicated to Indian traditions, Māyā connotes a "magic show, an illusion where things appear to be present but are not what they seem". Māyā is also a spiritual concept connoting "that which exists, but is constantly changing and thus is spiritually unreal", and the "power or the principle that conceals the true character of spiritual reality". Maya simply means that all matter is an illusion of the mind.

NOTES:
From section XLIV (On the Nature of Maya) from the Lankavatara Sutra (translated from Sanskrit by D T Suzuki):
Said the One: "Further, Mahamati, Maya is not an unreality, because it has the appearance of reality; and all things have the nature of Maya."
Said Mahamati: "Is it, that all things are like Maya because Maya is something imagined and clung to as having multitudinousness of individual forms? Or is it due to the incorrect imagining of individual forms? If all things have the likeness of Maya because Maya is something imagined and clung to as having multitudinousness of individual forms, then things are not like Maya. Why? Because forms are seen in the multitudinousness of individual signs not without due causes. If they ever appear without due causes, assuming the multitudinousness of individual signs and shapes, then they would be like Maya. For this reason, things are like Maya is not because they are both alike in being imagined and clung to as having multitudinousness of individual signs.
Said the One: "It is not, Mahamati, that all things are Maya because they are both alike in being imagined and clung to as having multitudinousness of individual signs, but that all things are like Maya because they are unreal.. ..Mahamati, all things assume individuality and generality according to the discrimination [of the Mind] itself. When the state of imagelessness is recognized, objects which are imagined and clung to as in possession of individual signs cease to assert themselves. Thus it is said: Maya is not without reality, because it has something resembling it; the reality of all things is talked of in a similar manner; they are unreal like a lightning-flash [appearing and disappearing] quickly, and therefore they are regarded as resembling Maya."