other
adj.adj. used to talk about a person or thing that is different from the one you already mentioned. You use it when there are more things in a group or a second choice available.
adj. referring to a person or thing that is distinct from one already mentioned or implied. Often used to indicate the remaining part of a set or an alternative category.
I have one red pen and three other pens.
If this hotel is full, we will have to look for other places to stay in the city.
While some researchers focused on the primary symptoms, other teams investigated the long-term psychological effects on the patient population.
Typically placed before a plural countable noun or an uncountable noun. When used with a singular countable noun, it usually requires a determiner like 'the', 'my', or 'another'.
I have other book to read.I have another book to read.When referring to a single alternative item, 'another' is used; 'other' requires a plural noun or a determiner like 'the other'.