Welcome to the forum

You're right about WR and CH. Linked to CH and WR, CR means combined ranking in doubles (i.e. the sum of both players' doubles rankings) and JWR means junior world ranking.

SE = special exempt, when a player who wasn't ranked high enough to make the main draw gets into the main draw with an exemption from having to play qualifying because they are still involved in singles in an equivalent or higher event on the day qualifying starts (that's the short version anyway, there are lots of detailed rules about SEs that vary slightly between types of tournament)

Other drawsheet abbreviations include:

PR = protected ranking (ATP-only), where a player who has been out injured is allowed to use their pre-injury ranking (or something close to it) to enter a certain number of tournaments in the months after they come back - it only affects entry, not seedings and again, the detailed rules are for more complex.

SR = special ranking - the WTA equivalent of the ATP's PR, following the apparent WTA policy of encouraging as much confusion as possible among fans.

JE = junior exempt - players who were highly-ranked in the last ITF year-end junior rankings are allowed to play in a small number of senior tournaments (the number and tournament levels available depend on their precise year-end junior ranking)

WC = wild card

If you come across others, as I'm sure you will, just post them on here and we'll try to answer. It might be worth making them into an alphabetical list one day, I guess.

thanks guys, hopefully I can make a bit more sense of the write-ups now.

is VOP an established TLA for Vandy's Outlandish Prediction ??

qWC is a wild card for qualifiers
MDWC is a wild card for the main draw.