Maltz was asked by a friend for the Klingon word for "cousin." He was happy to oblige, but before he got to "cousin," he said he needed to explain several other kinship terms.
There are four words for "aunt." me' is used to refer to one's mother's sister; 'e'mam is one's father's sister. An aunt by marriage (the wife of one's parent's brother) is either me'nal (mother's brother's wife) or 'e'mamnal (father's brother's wife).
Similarly, there are four words for "uncle." One's mother's brother is 'IrneH and one's father's brother is tennuS. The husband of one's mother's sister is 'IrneHnal, and the husband of one's father's sister is tennuSnal.
Now on to "cousin." The child of one's tennuS or one's me' is called a tey', while the child of one's 'IrneH or one's 'e'mam is called a lor. But these words are also used for "nephew" and "niece." A man will use tey' to refer to the child of his brother and lor to refer to the child of his sister, while a woman uses these terms the other way around: tey' is the child of her sister and lor is the child of her brother. To specify gender, loD "male" and be' "female" are added: tey'loD and lorloD mean "nephew, male cousin"; tey'be' and lorbe' mean "niece, female cousin."
If it is necessary to make a distinction between a nephew/niece and a cousin, one simply describes the relationship. For example: loDnI' puqloD "brother's son, nephew"' me' puqbe' "mother's sister's daughter, aunt's daughter, cousin." Unless specifically distinguishing between two individuals or explaining exactly how one is related to someone else, however, tey' and lor are much more common.
(Maltz speculated that there may be some connection between the noun tey' "cousin, nephew, niece" and the verb tey' "confide," since, at least according to Maltz, one tends to be closer to, and therefore more likely to confide in, one's tey' than one's lor.)
In addition to the specific terminology referring to cousins and siblings' offspring, there are four words that are more general in scope.
yur is used for a more distant cousin or niece or nephew. This would include second cousins, grandnephews, and the like. yur is not used to refer to a lor or a tey', though the plural yurpu' may be used to refer to a group consisting of a lor or tey' or two along with some other, more distant relatives.
vIn, in its plural form vInpu', is used for a group consisting of at least one lor and at least one tey' and no one who is not a lor or a tey'. Thus vInpu' may be translated "cousins, nieces, nephews." If it's not a mixed group, then, of course, the plural forms of lor and tey' would be used (lorpu', tey'pu'). vInpu' might also be used if the speaker is unsure about the makeup of the group (but sure enough to know that vInpu' is a better choice than yurpu'). The singular form, vIn, is also sometimes used in place of lor or tey' when focusing on the vIn as a member of a group of vInpu' as opposed to his or her specific relationship to the speaker.
'e'nal refers to someone who married into the family, but does not specify the exact relationship.
tuqnIgh is used to refer to any member of a house. Thus, qeng tuqnIgh is "a member of the House of Kong," and tuqnIghwI' is "a member of my house."
While he was at it, Maltz offered several other kinship terms, but he made it clear that his list was not exhaustive (he left off words for "great-grandmother," "great- grandson," "great aunt" and the like). puqnI' is the word for "grandchild." If it is necessary to specify gender, loD or be' is added: punI'loD "grandson," puqnI'be' "granddaughter." Finally, there is a special word for "firstborn": ghubDaQ.