Define esterification with an example.

Hint: In chemistry, an ester is a chemical compound derived from an acid (organic or inorganic) in which at least one $-OH$ (hydroxyl) group is replaced by an $-O-$alkyl (alkoxy) group. Usually, esters are derived from the substitution reaction of a carboxylic acid and an alcohol. One specific reaction for the formation of ester is known as esterification

Complete step by step answer:
The definition of esterification reaction is as follows.
Esterification is the process of mixing an organic acid (RCOOH) with an alcohol (ROH) to make an ester (RCOOR) and water; or a reaction leading to the formation of a minimum of one ester product. Ester is obtained by an esterification reaction of an alcohol and an acid.
The general reaction for esterification is as follows.
\[RC{{O}_{2}}H\,+\,{{R}^{'}}OH\,\rightleftharpoons \,RC{{O}_{2}}{{R}^{'}}\,+\,{{H}_{2}}O\]
An example for the esterification reaction is as follows.
$C{{H}_{3}}COOH\,+\,{{C}_{2}}{{H}_{5}}OH\,\to \,C{{H}_{3}}COO{{C}_{2}}{{H}_{5}}\,+\,{{H}_{2}}O\,$

Additional information:
An acid is an organic acid that contains a carboxyl group ($-COOH$) attached to an R-group. The overall formula of an acid is $R-COOH$, with $R$ pertaining to the alkyl group. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids.
Alcohols are the family of compounds that contain one or more hydroxyl (-OH) groups attached to a single bonded alkane. Alcohols are represented by the overall formula$-OH$. Alcohols are important in chemistry because they can be converted to and from many other sorts of compounds

Note: Ester names are derived from the parent alcohol and therefore the parent acid, where the latter could also be organic or inorganic. Esters derived from the only carboxylic acids are commonly named consistent with the more traditional, so-called "trivial names" e.g. as formate, acetate, propionate, and butyrate, as against the IUPAC nomenclature methanoate, ethanoate, propanoate and butanoate.