As has been mentioned previously, Arabic is based on a tri-lateral root system. One of the beautiful characteristics of Arabic is that it will take this three letter root and give it the meaning of a time or place. There are other words whose inherent nature is to indicate time and place. Often the two are confused with one another. Thus, there are some terminology that we need to learn:

  1. ظرف زمان – a word that inherently indicates time (Ex. قَبْلَ – before)
  2. ظرف مكان – a word that inherently indicates place (Ex. فَوْقَ – above)
  3. اسم زمان – a word that is derived to indicate time (Ex. مَغْرِبٌ – time of sunset)
  4. اسم زمان – a word that is derived to indicate place (Ex. مَسْجِد – place of prostration)

There are a few differences between ظرف زمان\مكان and اسم مكان\زمان

1. Generally, ظرف are words whose default state is منصوب, meaning it takes a fatha on the end. (Ex. قَبْلَ – before)
اسم مكان\زمان default state is مرفوع, meaning it takes a dhamma. (Ex. ٌمَسْجِد – place of prostration)

2. ظرف takes a مضاف إليه. In other words, it sounds incomplete without a word coming after it. (Before what? Before noon قبل الظهر, Before lunch, etc. ) ***
اسم مكان\زمان don’t require a مضاف إليه.

3. ظرف are a set of words one needs to memorize.
فَوْقَ – above
أَيْنَ – where?
تَحْتَ – below
أَمَامَ – in front

اسم مكان\زمان usually follows the pattern of (مَفْعِل\مَفْعَل)  where the فعل letters can be replaced with any three root letters.
Examples:
مَدْخَل – a place of entering (entrance)
مَخْرَج – a place of leaving (exit)
مَدرَسة – a place of studying (school)
مَقْبَرة – a place of graves (graveyard)
مَغْرِب – time of sun setting (sunset)

One of the reasons these differences need to be explained is because some may explain اسم مكان\زمان as a ظرف because they share the meaning of time and place, but as can be seen above, they differ grammatically in many different ways.

InshAllah this helps,

Faraz

*** If the مضاف إليه drops then the ظرف will take a single dhamma to indicate that it dropped.
بَلْ بَدَا لَهُم مَّا كَانُوا يُخْفُونَ مِن قَبْلُ 6:28
But what they concealed before has [now] appeared to them.