العدسة مقاومة للخدش.

Because this is a nominal sentence in Arabic. In the present tense, Arabic usually does not use a separate word for is / are.

So:

• العدسة = the lens
• مقاومة = resistant
• للخدش = to scratching / to scratches

Together, the sentence naturally means The lens is scratch-resistant or The lens is resistant to scratching.

If you wanted a past-tense version, Arabic would use a verb such as كانت:

• كانت العدسة مقاومة للخدش = The lens was scratch-resistant.

Because it describes العدسة, and العدسة is a feminine singular noun.

In Arabic, adjectives must agree with the nouns they describe in:

• gender
• number
• definiteness

Since العدسة is feminine singular, the adjective must also be feminine singular:

• masculine: مقاوم
• feminine: مقاومة

So:

• زجاج مقاوم للخدش = scratch-resistant glass
• عدسة مقاومة للخدش = a scratch-resistant lens

A good clue is the ة at the end of both العدسة and مقاومة, which often marks feminine singular forms.

Here it is functioning as an adjective, meaning resistant.

That can confuse learners because مقاومة can also be a noun in other contexts, meaning resistance.

Compare:

• العدسة مقاومة للخدش
  Here مقاومة = resistant (adjective)

• المقاومة شديدة
  Here المقاومة = the resistance (noun)

So the form is the same, but the role depends on the sentence.

Because the adjective مقاوم / مقاومة is commonly followed by لـ, which in this context gives the meaning resistant to.

So:

• مقاوم للماء = water-resistant
• مقاوم للحرارة = heat-resistant
• مقاومة للخدش = resistant to scratching / scratch-resistant

This is just the normal pattern Arabic uses with this adjective. English learners often expect a direct equivalent of to, and in Arabic that is usually expressed here with لـ.

Because the preposition لـ joins directly to the following word. When it comes before الـ, the result is written together:

• لِ + الخدش → للخدش

This is very common in Arabic spelling.

So:

• للماء = to water / for water
• للحرارة = to heat
• للخدش = to scratching / to scratches

In pronunciation, it is typically read as lil-khadsh.

Because Arabic often uses the definite article in places where English uses a more general expression.

Here الخدش does not mean one specific scratch. It refers to the concept of scratching or scratch damage in a general sense.

So للخدش is best understood as:

• to scratching
• to scratches
• against scratching

This kind of definite noun is very common in Arabic when speaking about a category or phenomenon in general.

Yes. In this sentence, that is often the most natural way to understand it.

The noun خدش can refer to:

• a scratch
• scratching
• scratch damage

So مقاومة للخدش can be interpreted as:

• resistant to scratches
• resistant to scratching
• scratch-resistant

Arabic often uses a singular noun in a general sense where English may prefer a gerund or a plural.

It is a simple nominal sentence:

• العدسة = the subject
• مقاومة للخدش = the predicate

More specifically:

• العدسة is the مبتدأ (topic/subject)
• مقاومة is the main part of the خبر (predicate)
• للخدش is attached to مقاومة and completes its meaning

So the whole structure is:

العدسة + مقاومة للخدش
= The lens + is resistant to scratching

In fully vocalized formal Arabic, it would be:

العَدَسَةُ مُقاوِمَةٌ لِلخَدْشِ

The endings are:

• العَدَسَةُ → -u because it is the subject of the nominal sentence
• مُقاوِمَةٌ → -un because it is an indefinite predicate
• لِلخَدْشِ → -i after the preposition لـ

In normal writing, these endings are usually not written, and in pause they are often not pronounced.

It is pronounced approximately al-ʿadasa.

A few notes:

• The first sound after al- is ع (ʿayn), which does not exist in English.
• The الـ is pronounced normally here because ع is not a sun letter.
• The final ة is pronounced as -a in pause: ʿadasa.

So the whole word is roughly:

• al-ʿa-da-sa

It is pronounced approximately al-khadsh.

Notes:

• خ is like a rough, throaty kh sound, similar to the ch in German Bach or Scottish loch
• دش at the end gives a cluster like -dsh

In the phrase للخدش, it is usually pronounced lil-khadsh.

Because both ع and خ are moon letters, not sun letters.

With moon letters, the l sound in الـ is pronounced clearly:

• العدسة = al-ʿadasa
• الخدش = al-khadsh

If the word began with a sun letter, the l would assimilate, as in:

• الشمس pronounced ash-shams

But that does not happen here.

Not literally in grammar, but it is close in meaning.

Arabic here is using an adjective, not a verb of action. So the idea is not that the lens is actively doing something right now, but that it has a property:

• مقاومة للخدش = resistant to scratching

So English translations like these are natural:

• The lens is scratch-resistant
• The lens is resistant to scratching

But The lens resists scratching is more of a looser paraphrase than a direct grammatical match.

Yes, you may see مضاد للخدش or مضادة للخدش in some contexts, especially in technical or marketing language, meaning something like anti-scratch.

But مقاومة للخدش is very natural and common for scratch-resistant.

The difference is roughly:

• مقاومة للخدش = resistant to scratching
• مضادة للخدش = anti-scratch

Both can work, but مقاومة للخدش is a very standard phrasing.

Because in this kind of sentence, the predicate is often indefinite.

So:

• العدسة = definite subject
• مقاومة = indefinite predicate

This is normal Arabic grammar. In fact, making the predicate indefinite often helps show that it is the predicate, not another noun being directly equated as a definite label.

Compare:

• العدسة مقاومة للخدش = The lens is scratch-resistant

If you said العدسة المقاومة للخدش, that would usually mean:

• the scratch-resistant lens

That is a noun phrase, not a full sentence.

This is an important difference:

1. العدسة مقاومة للخدش
   This is a complete sentence:
   The lens is scratch-resistant.

2. العدسة المقاومة للخدش
   This is a noun phrase:
   the scratch-resistant lens

Why?

• In the sentence, مقاومة is an indefinite predicate.
• In the noun phrase, المقاومة is definite and acts like an adjective modifying العدسة.

So one is a statement, and the other is just a description of a noun.

Yes, عدسة is treated as a feminine noun in standard Arabic.

That is why you say:

• عدسة صغيرة
• عدسة نظيفة
• عدسة مقاومة للخدش

The adjective must be feminine to match it.

Usually Arabic expresses this idea with a phrase rather than one compact compound adjective.

So instead of one built-in word like English scratch-resistant, Arabic naturally says:

• مقاوم للخدش / مقاومة للخدش
• or sometimes مضاد للخدش / مضادة للخدش

This is very normal. Arabic often uses an adjective + prepositional phrase where English uses a hyphenated compound.