Compound nouns are usually two or more words put together to create a new noun.examples sunflower, blackboard etc. Where as collocations are words or phrases which are commonly used together. examples heavy rainfall, deep sleep, to make bed etc.Could you update me a little more about the same?
The collocation is a sequence or juxtaposition of words or terms that usually co-occur / go together in a sentence. For example, you make the bed, but you do your homework.
1) collocations with make : make breakfast, make a mistake, make a decision, make love, make room, make a noise, etc.
2) collocations with do : do the shopping, do the dishes, do your homework, do your hair, do a course, do a favour, etc.
But compound nouns or nominal compounds are different things.
More than one simple word or primary word or base word or root word combine together to form a compound word.
(I) ready + made = readymade (compound adjective).
(ii) full + fill = fulfil (compound verb).
(iii) moon + light = moonlight (compound noun or nominal compound)
Compound nouns are also formed by simple words of different parts of speech :
He (pronoun) + goat (noun) = he-goat (compound noun)
Pick (verb) + pocket (noun) = pickpocket (compound noun)
Over (adverb) + production (noun) = over-production (compound noun).
Up (preposition) + keep (verb) = upkeep (compound noun).
In (preposition) + come (verb) = income (compound noun).
Draw (verb) + back (adverb) = drawback (compound noun).
Hear (verb) + say (verb) = hearsay (compound noun).
Sometimes a compound noun consists of three words. Such compound nouns usually have the following structure:
Noun + V-ing / V - p.p. + Noun.
e.g., God-fearing person ( = Person who fears God).
Machine-made clothes ( = Clothes made by machine).
Compound nouns can be written in different ways :
1) with no space between two words : footpath.
2) with hyphen : tea-set.
3) with space between the words : mango tree.
4) with hyphen between the first & the second words : Tea-growing area.
5) without any hyphen : Calcutta bus routes.