No, because sick is an adjective and there are not plural forms for adjectives. However, if you changed it into a noun (i.e., sickness) then you could make it into sicknesses.
Some compound words that contain the word sick are:
airsickcarsickheartsickhomesicklovesicksickbaysickoutsickroom
Seasick.
No It's not a compound word
No, important is not a compound word.
Upwards is a compound word.
There is no compound word.A compound word is a word like bus-stop.Husban is spelt like this husband
Upstairs is a compound word, so it is one word.
No it is not a compound word
Mango is not a compound word.
άρρωστος the word sick
A non compound word is , a word with one word not two . For a example a compound word is snowflake. An non compound is hot cheetos.
No, unpack is not a compound word because "un" is not a word a compound word is a word that has two words in it.