to meddle, esp. for the purpose of altering, damaging, or misusing (usually fol. by with )

Someone has been tampering with the lock.

to make changes in something, esp. in order to falsify (usually fol. by with )

to tamper with official records.

to engage secretly or improperly in something.

to engage in underhand or corrupt dealings, esp. in order to influence improperly (usually fol. by with )

Any lawyer who tries to tamper with a jury should be disbarred.

verb

leave alone

verb

busybody * , butt in * , change , cook , cut , damage , destroy , diversify , doctor , fiddle with , fool , horn in , interlope , interpose , intrude , irrigate , manipulate , meddle , mess around with , monkey around , muck about , phony up , plant * , poke nose into , spike * , tinker , vary , water * , buy , buy off , corrupt , fix , get to , have , influence , lubricate , reach , rig , square * , fiddle , mess , alter , bribe , interfere , intervene , machinate