Correct spelling for the English word "oncostman" is [ˈɒnkɒstmən], [ˈɒnkɒstmən], [ˈɒ_n_k_ɒ_s_t_m_ə_n] (IPA phonetic alphabet).
The word "oncostman" is derived from the combination of two terms: "oncost" and "man".
1. Oncost: The term "oncost" is a colloquialism that originated in Scotland and Northern England. It is a noun used to refer to additional or miscellaneous expenses incurred during a project or undertaking, especially in the building or construction industry. Some examples of oncosts are overhead expenses, wages, taxes, and other costs that are not directly related to the production of goods or services.
2. Man: The word "man" simply refers to a human being, specifically an adult male.
When these two terms are combined, "oncostman" refers to an individual, typically in the construction industry, who is responsible for estimating and managing the additional costs or expenses associated with a project.