give the high sign

Strongest matches

• alarm
• forewarn
• inform
• notify
• tip off

Strong matches

• flag
• signal
• tip

Weak matches

• put on guard
• wave flag

Strongest matches

• admonish
• alert
• exhort
• forewarn
• urge

Strong matches

• flag
• tip

Weak matches

• give the lowdown on
• pull one's coat
• put one wise
• tip off
• wave a red flag
• wise one up

Strongest matches

• admonish
• apprise
• dissuade
• tip off

Strong matches

• advise
• alarm
• alert
• flag
• portend
• telegraph
• tip

Weak matches

• forbode
• give fair warning
• premonish
• pull one's coat
• put a bug in one's ear
• put on guard
• put one wise
• wave a red flag

Strong matches

• flag
• gesticulate
• indicate
• mime
• motion
• pantomime
• sign
• signal
• wave

Weak matches

• act out
• use one's hands
• use sign language

Strongest matches

• address
• advise
• alert
• caution
• hint
• inform
• instruct
• notify
• order
• predict
• prepare
• prompt
• recommend
• remind
• signal
• suggest
• summon
• tell
• threaten
• urge

Strong matches

• acquaint
• admonish
• advocate
• apprise
• clue
• counsel
• deprecate
• direct
• dissuade
• enjoin
• exhort
• forbid
• forearm
• forewarn
• guide
• post
• prescribe
• remonstrate
• reprove
• tip

Weak matches

• clue in
• cry wolf
• fill in
• give fair warning
• give warning
• lay it out
• make aware
• put on guard
• tip off
• wise up