boost

[1]	lift , hike , shove/push up/upward(s) , hike up , raise
[2]	encourage , promote , help , aid , support , assist , improve
[3]	increase , promote , raise , advance , further , encourage
[4]	advance , supercharge

[1]	encouragement , lift , shove/push up/upward(s) , (Colloq) leg up , rise , raise
[2]	encouragement , rise , help , hike , cost increase , aid , assistance , support
[3]	increase , rise , (US) raise , hike