العدسة صغيرة.

Because Arabic usually omits the present-tense verb to be in sentences like this.

So العدسة صغيرة literally looks like the lens small, but it means The lens is small.

This kind of sentence is called a nominal sentence in Arabic.

• العدسة = the subject
• صغيرة = the predicate/description

If you wanted was, Arabic would normally use كان and its forms.

It is a complete sentence.

In Arabic grammar:

• العدسة is the subject (مبتدأ)
• صغيرة is the predicate (خبر)

So this is not just a noun phrase. It is a full statement.

Compare:

• العدسة صغيرة = The lens is small
• العدسة الصغيرة = the small lens

That second one is a noun phrase, not a full sentence.

Because العدسة is a feminine noun, and Arabic adjectives must agree with the noun they describe or refer to.

So:

• masculine: صغير
• feminine: صغيرة

Since عدسة is feminine, the predicate must also be feminine: صغيرة.

A helpful clue is the ending ة on عدسة, which often marks a feminine noun.

Because here صغيرة is the predicate of the sentence, not an adjective inside a noun phrase.

In Arabic, the predicate in a sentence like this is usually indefinite, so it does not take ال.

So:

• العدسة صغيرة = The lens is small
• العدسة الصغيرة = the small lens

This is a very important distinction in Arabic.

Because in Arabic, words that describe a noun usually come after the noun, not before it as in English.

So Arabic prefers:

• عدسة صغيرة = a small lens

not a structure like small lens with the adjective first.

In العدسة صغيرة, the second word is technically the predicate of a sentence, but it still comes after the subject.

That letter is called taa marbuuTa (ة).

It often marks a word as feminine.

In this sentence:

• عدسة is feminine
• صغيرة is the feminine form of small

In pronunciation, ة usually sounds like -a when you stop on the word:

• عدسة ≈ ʿadasa
• صغيرة ≈ ṣaghīra

In very careful formal pronunciation, when endings are fully pronounced, it can sound like -at before case endings.

The fully vowelled form is:

العدسةُ صغيرةٌ

In full formal grammar, both words are in the nominative here:

• العدسةُ = subject
• صغيرةٌ = predicate

In normal unvowelled writing, those short vowels are usually left out, so you just see:

العدسة صغيرة

A careful full reading is:

al-ʿadasatu ṣaghīratun

But in pause, which is very common when reading a short sentence by itself, you will often hear something closer to:

al-ʿadasa ṣaghīra

A few pronunciation notes:

• ʿ represents ع
• ṣ represents an emphatic s
• gh represents غ, a back-of-the-throat sound

Yes.

In العدسة, the ل of ال is pronounced because ع is a moon letter, not a sun letter.

So you say:

al-ʿadasa

not something like aʿ-ʿadasa.

This is different from words beginning with sun letters, where the l assimilates, such as:

• الشمس pronounced ash-shams

ع is one of the trickiest Arabic letters for English speakers.

It is called ʿayn and is pronounced deep in the throat. English does not really have an exact equivalent.

A practical beginner tip:

• do not ignore it completely
• try to make a brief constriction in the throat before the vowel

So العدسة begins something like:

al-ʿa...

Even an approximate ʿayn is better than dropping it entirely.