Back in the day, IBI used to include a list of reserved words in their documentation but the only thing I can find are listings for SQL Translator and MAINTAIN.

Do we need to be careful with field names, HOLD file names, etc. anymore?

If so, then where is list since I couldn't find it on IBI's site.

Best I could find, However it does not appear to be complete

 
This is a list of "Watch" Words for FOCUS.
  Their use should be avoided as fieldnames, aliases,
  casenames, segnames, filenames, computed fields, etc.
  NOTE:  A "watch" word may not be reserved in all situations.
  -----------------------------------------------------------------------------
   A            CREATE       FOOTING      LOG          PRINT        SUMMARIZ
   ABS          CRTFORM      FOR          LST          PROMPT       SUPPRINT
   AUTOPATH     AUTOINDEX    EXTSORT
 
   ACCESS       CT           FORM         LT           QUIT         TABLE
   ACROSS       DBA          FORMAT       MARK         RANKED       TABLEF
   ADD          DECODE       FREEFORM     MATCH        READLIMIT    TED
 
   AGAIN        DECRYPT      FROM         MAX          REBUILD      TEMP
   ALL          DEFINE       FST          MDISC        RECAP        TLOCATE
   ALLOC        DEL          GE           MDY          RECOMPUTE    TO
 
   ANALYSE      DELETE       GOTO         MDYY         RECORDLIMIT  TOP
   AND          DESCRIPTION  GRAPH        MIN          RECTYP       TOT
                                          MAINTAIN
                                          MORE
   ANOVA        DIS          GT           MODIFY       RECTYPE      TOTAL
   AS           DISPLAY      GTREND       MOVE         REORG        TRACE
   ASQ          DMTY         HEADING      MSG          REPLACE      TYPE
 
   AVE          DMY          HIGHEST      MT           REPLOT       UNDERLINE
   B            DMYY         HIST         MTDY         RESTRICT     UP
   BACK         DUPL         HOLD         MULTR        RETYPE       UPDATE
 
   BIN          E01          I            N            ROLLBACK     USAGE
   BINS         E02          IF           NE           ROW          USE
   BY           E03          IN           NEXT         ROW-TOTAL    USER
 
   C1           ECHO         INCLUDE      NOMATCH      ROWS         VALIDATE
   C2           EDIT         INCLUDES     NOPRINT      RPCT         WHEN
   C3           ENCRYPT      INDEX        NOT-FROM     SAVB         WHERE
 
   CDN          END          INPUT        NOTOTAL      SAVE         WITHIN
   CHANGE       EQ           INT          OFFLINE      SCAN         WRITE
   CHECK        EX           INVALID      OM           SEG          X1
 
   CLEAR        EXCEEDS      IS           OMITS        SEGMENT      X2
   CNT          EXCLUDES     IS-LESS-THAN ON           SEGNAME      X3
   CO           EXEC         IS-MORE-THAN ONLINE       SET          XFER
 
   COLUMN       EXIT         IS-NOT       OR           SHOW         Y
   COLUMN-TOTAL EXPLAIN      JOIN         OVER         SKIP-LINE    YMD
   COLUMNS      EXSMO        JUMP         PAGE         SQRT         YMTD
 
   COMBINE      FACTO        LAST         PAGE-BREAK   ST           YYMD
   COMMIT       FIELDNAME    LE           PANEL        STATSET
   COMPILE      FILE         LET          PASS         STOR
 
   COMPUTE      FIN          LINES        PAUSE        STORE
   CONSULT      FINISH       LINK         PCT          SUB-TOTAL
   CONTAINS     FIXFORM      LIST         PICKUP       SUBFOOT
 
   CONTINUE     FML          LOC          PIE          SUBHEAD
   CORRE        FOCCURRENT   LOCATE       POLRG        SUBTOTAL
   COUNT        FOCUS        LOCATION     POST         SUM
   DST          REPAGE       MULTI-PATH

My experience is that if I use the Editor within the application the color with some words change to RED. If so I won't use it.