It's on the new words page for the qepHom 2016: http://www.kli.org/activities/qepmey/qephommey/qephom-2016/
There are two words for "share." When A shares something (C) with B, the verb to use is bon ("share with") and the construction is B-vaD C bon A (with appropriate verb prefixes depending on what A and C are). In this case, C belongs to or is controlled by A and A chooses to share it with B. When A and B share something with each other (share some gagh, say), the verb to use is lIn ("share") and the construction is C lulIn A B je (or C lIn A B je if C is plural, and, again, with appropriate verb prefixes). In this case, the speaker is noncommittal about whether A or B is the one who decided to do the sharing with the other.
There is an idiomatic expression: lInchuq "share each other."
This is not a euphemism, but Maltz admitted it's a little risqué. lInchuq ("they share each other") means that they (whoever is being talked about) have a physical relationship of some sort. The phrase is general — it doesn't imply anything about exactly what they do physically. It also doesn't necessarily mean that they are doing something right now (at the time of speaking).
The relationship could be relatively light (a little nibbling) or heavier (really biting) or beyond (Maltz thought that Terrans might find that part a bit risqué).
As with other verbs with -chuq, the prefix has to indicate a plural subject and no object:
malInchuq
SulInchuq
qurgh