To help keep your writing crisp and precise, observe the distinctions between each pair of similar or closely associated words below:
1. Admission/admittance: Admission is the act of being admitted, or allowed to join or enter; admittance is almost identical in meaning but is usually associated with permission (or lack thereof).
2. Avocation/vocation: An avocation is a hobby or pursuit, as distinct from a vocation job or career. The former is derived from a word with the literal meaning of “called away,” and the latter is an antonym; it literally means “calling” and is related to the word voice.
3. Bloc/block: Bloc refers to an alliance of people, groups, or countries. It is the French version of block, which may be but seldom is used to refer to the same concept.
4. Bonds/bounds: A bond, among other meanings, is a restraint, so it is similar in meaning to bound, which means “extent, or limit” (as in boundary). But they are complementary, not interchangeable; one is bound with bonds.