The best replacement for contribution is donation.

The best alternatives to contribution are rated as following:
★★★★★  donation
★★★★  defined benefit
★★★  indemnification
★★★  indemnity
★★  contributions
★★  distribution
★★  loan
★★  gross margin
★★  attribution
★  grant
★  defined benefit plans
★  exchange transaction
★  in kind donation
★  defined benefit plan
★  achievement
★  traditional income statement
★  expenditure
★  sponsorship
★  absorption approach
★  shareholder loan
  exchange transactions
  profit margin
  benefit pension plan
  ira contribution
  defined benefits
  claim for indemnity

Your alternative for contribution is not listed? Suggest!
Speaking about contribution, one probably shouldn't forget about 401k.

Other search terms related to contribution and their ratings are:

★★★★★ 401k
You have in mind a companion for contribution and it is not yet here? Propose!

Google Trends

Scale is based on the average worldwide traffic of contribution in all years. Click on graph for more.
defined benefit