A person who accounts, reckons, or calculates. Also: one who presents an account (of money, responsibilities, etc.). Cf. accountant, n., counter, n.2…

One who works out arithmetical problems; a proficient in the science of numbers.

A mathematician; an arithmetician; an accountant.

A person skilled in calculation or computation; = computer, n. 1. Now chiefly historical.

A person who does sums or arithmetic. Obsolete (in later use colloquial or regional).

A person who makes calculations or computations; a calculator, a reckoner; spec. a person employed to make calculations in an observatory, in…

One who casts or reckons with counters; ‘a word of contempt for an arithmetician’ (Johnson).

A person who calculates or reckons something. Cf. computer, n. 1.

A person who counts or enumerates; a reckoner, calculator. Also: one who can count or reckon well (poorly, etc.). Now rare.

A calculator. Obsolete.

A person who attaches importance to or is concerned with numbers.

One who ciphers.

An arithmetician. Obsolete.

A person who makes calculations or computations; = computer, n. 1, computator, n. 1.

One who casts up figures (see figure, n. 19).

colloquial. A person, machine, or system with a capacity for performing complex or lengthy operations with numerical data, computer code, etc…