Academic writing demands a formal tone characterized by careful language choices to convey ideas to readers as precisely and unambiguously as possible. Colloquial language, defined as language that is “normally restricted to informal (especially spoken) English” (Burchfield, 2004), does not satisfy this need for exactness of expression.
Instead, as Pam Peters (2007) says of colloquialisms, they “undermine the serious effect you want to have on the reader. Your writing should not appear casual, imprecise or gloss over details.” Therefore, to create the best impression when writing academically, it is recommended to find formal equivalents for any colloquialisms you may otherwise be tempted to use.
What to Avoid
Some types of colloquial language are obviously inappropriate for use in academic writing, such as slang (e.g. “till” instead of “until”) or vulgar expressions. However, less obviously, you should also avoid the following.
For example: “time will tell” and “as luck would have it”.
These expressions are commonly used in speech, but for formal writing, they lack both the specificity of meaning required to lend accuracy to your writing, and the originality to make your writing more interesting.
For example: “a drop in the ocean” and “cut to the chase”.
These expressions are extremely common in speech, but they pose important problems in academic writing. First, as with clichés, these expressions lack specificity of meaning. Second, and even more problematically, because idioms cannot be understood literally, using them risks misinterpretation of your meaning by readers without the necessary language skills.
For example, “very”, “so” and “even”.
It is common to use filler words to add emphasis and rhythm in speech. However, such words are unnecessary in academic writing and detract from its effectiveness.
Finding Formal Equivalents
Between using Google search and consulting a good dictionary, a suitable formal equivalent to any colloquial expression will always be to hand. For example, to find a formal equivalent of “to hand”, a simple search of Google search for “define to hand” produces the definition of “within easy reach”. Likewise, using the online Macquarie Dictionary (available through an annual paid subscription), a search for “hand” returns a result with a list of idioms that use the word hand. Number 95 in the list gives the definition of “to hand” as “within reach”.
Note that a Google search for a definition will return results from several online dictionaries, some of which are better than others. Try to use only respected online dictionaries, such as Merriam Webster, the Oxford Dictionary, the Oxford Learner’s Dictionary, the MacMillan Dictionary, the Collins Dictionary or the Cambridge Dictionary.